SKETCH OF THE 
GEOLOGY 
AND 
PALAEONTOLOGY 
OF THE 
VALLEY OF MACKENZIE RIVER. 
BY 
F. B . M E E K. 
Extracted from the Trans. Chicago Acad. 8ci. Vol. 1. 
a f&w: 
t / CHICAGO ACADEMY OF SCIENCES. 
Art. III. Remarks on the Geology of the valley of Mac- 
kenzie River, with figures and descriptions of Fossils from 
that region, in the Museum of the Smithsonian Institution, 
chiefly collected by the late Robert Kennicott, Esq. By 
F. B. Meek. 
For what is known of the geology of Mackenzie river valley, 
we are mainly indebted to the distinguished arctic explorer 
and naturalist, Sir Joikx Richardson, and Mr. A. K. Isbister. 
The first of these gentlemen, while acting as Surgeon and 
Naturalist of Sir John Franklin’s overland expedition to the 
Polar Seas, during the years 1825-6-7, collected much inter- 
esting information in regard to the geological formations at 
various localities along Mackenzie river and its tributaries, 
all of which is published in the form of an appendix to Sir 
John Franklin’s narrative of his expedition. Again, in 1848, 
he descended Athabasca, Slave and Mackenzie rivers, in com- 
mand of an expedition sent out by the British Government in 
search of the lamented Sir John Franklin and his unfortunate 
companions. During this expedition he had an opportunity 
to examine various localities not previously visited, and the 
additional information thus obtained is published in his inter- 
esting “Journal of a Boat Voyage through Prince Rupert’s 
Land.” Subsequently Mr. Isbister spent some time in these 
distant northern regions, during which he visited the Rocky 
Mountains, and other portions of the country bordering on 
Mackenzie river; and in Volume NI of the Quarterly Jour- 
nal of the Geological Society of London, he published, in 
1855, an interesting paper giving the results of his own obser- 
vations, and a map on which he colored all that was then 
known, from the examinations of Sir John Richardson and 
others, of the geology of the Hudson’s Bay Company’s territo- 
ries, Russian America, Ac. 
As miglit be expected, however, investigations of tliis 
nature in so vast a country, the whole surface of which is 
locked in ice and snow for seven or eight months of the year, 
when made incidentally by parties traveling hastily in pursuit 
of other objects, must afford us but meagre and isolated 62 
TRANSACTIONS OF THE 
information. Many years must elapse before much can be 
known respecting the details of the geology of this immense 
area, so seldom visited by scientific observers. Hence any 
additional information of this kind, especially when derived 
from an examination of fossil remains, can scarcely fail to be 
acceptable to those interested in the progress of geological 
science. 
The specimens upon which this paper is based, were mainly 
obtained at some seven or eight localities along Mackenzie 
river and its tributaries, between Clear Water river (lat. 56 
deg. 30 min. north, and long. Ill deg. west), and the Arctic 
Ocean. They were collected by the late Major Robert Iven- 
nicott, who visited this northern country under the auspices of 
the Smithsonian Institution, and by Messrs. R. W. McFarlane 
and B. R. Ross, of the Hudson’s Bay Fur Company. To the 
zeal of these gentlemen, and the liberality of the Smithsonian 
Institution, I am indebted for the privilege of examining this 
interesting collection. I am also under obligations to Mr. 
Kennicott, and the other gentlemen mentioned, for interesting 
information respecting the general geological and topographi- 
cal features of this remote country, that could not have been 
derived from an examination of the specimens without the aid 
of their notes and observations. 
Tlie most southern locality from which any of these speci- 
mens were obtained, is near the month of Clear Water river, 
a small stream not more than sixty or seventy miles in length, 
flowing westward into the Athabasca, one of the principal 
tributaries of Mackenzie river. According to Sir John Rich- 
ardson, this little stream is elevated about 900 feet above the 
sea. Immediately east of its source, the dividing ridge be- 
tween it and Methy lake rises abruptly to an elevation of 
about 800 feet above the ClearWater valley, and some 188 
feet above Methy lake. This ridge, elevated near 1,700 feet 
above the sea, 'trends in a north-easterly and south-westerly 
direction, and forms the divide between the waters flowing 
eastward into Hudson’s Bay and those flowing into 
the Athabasca, and thence through Slave and Mackenzie 
rivers, and the intervening lakes, to the Arctic Sea. It forms 
one of the most formidable obstacles in the way of trade and 63 
CHICAGO ACADEMY OF SCIENCES. 
travel between Lake Superior and Hudson’s Bay and the 
valley of Mackenzie river; all the supplies for the Fur Com- 
pany’s numerous trading establishments along Mackenzie 
river and its tributaries, and their returning furs, having to 
be here transported twelve miles across by land between 
Methy lake and the Clear Water. The eight hundred feet of 
space between the summit of this ridge and Clear Water 
valley, judging from Sir John Richardson’s observations, is 
occupied by a heavy arenaceous deposit, reposing upon a dark 
bituminous shale, beneath which occur, along the Clear Water 
and Athabasca rivers, beds of yellowish gray limestone of a 
more or less laminated structure. The arenaceous deposit ap- 
pears to be more than six hundred feet in thickness. Salt and 
sulphur springs may be seen at several places issuing from the 
limestone; and the overlying shales and sandstones, particu- 
larly the former, as well as the limestone, are highly charged 
with asphaltum or mineral pitch, at various places along the 
Athabasca and Mackenzie rivers. 
At the month of Clear Water river, and some miles above, 
high bluffs are seen along its north shore, composed at the 
base of a concretionary, and at places compact limestone, 
surmounted by 150 or more feet of dark bituminous shale, 
above which the hills are composed of sand or sandstone. This 
dark shale Sir John Richardson and Mr. Isbister refer to the 
horizon of the Marcellus shale of the New York geologists. 
The beds of impure argillaceous limestone seen beneath it, 
form the banks of Athabasca river for more than thirty miles 
below the mouth of the Clear Water, and are at places consid- 
erably stained with bituminous matter. At one place, near the 
water’s edge, Sir John Richardson collected from one of the 
layers the following fossils, viz. “ Producti, Spirifers, an 
Orthis resembling 0. resupinata, Terebratula reticularis and a 
Pleurotomaria,” which were referred by Mr. Woodward to 
the Devonian System. 
The fossils now before me, collected from this limestone by 
Mr. Kennicott, at the mouth of the Clear Water, are a small 
turbinate coral, apparently a Cysteophyllum, Productus dissimi- 
lis Hall, Strophodonta demissa Conrad (sp.), Orthis ioivensis 
Hall? (large variety), Atryjpa reticularis Lin. (sp.), Cyrtina 64 
TRANSACTIONS OF THE 
Billingsi Meek, an Aviculopectenf and a cast of a univalve, 
apparently a depressed Plemvtomaria. 
The fine Orthis I have here referred with some doubt to O. 
iowensis, is the same mentioned by Sir John Richardson, as it 
resembles 0. resupinata closely, though clearly distinct. It 
agrees exactly with 0. iowensis from the Hamilton group in 
Iowa, excepting that it attains a larger size, and the larger 
specimens have, in the front margin, a much deeper and nar- 
rower sinus, though there are in the collection individuals 
showing various gradations between these and others agreeing 
in all respects with 0. iowensis. The specimens of Atrypa 
reticularis are numerous and belong to the large dilated 
variety so common in the Hamilton group of New York; 
while those of Strop>hodonta agree exactly with specimens from 
that horizon in New York and localities further west. The 
specimens I have referred to Productus dissimilis are not in 
a very good state of preservation, but so far as their charac- 
ters can be made out, they seem to be in all respects identical 
with P. dissimilis, from the Hamilton group in Iowa. 
From this assemblage of fossils, particularly when viewed 
in connection with others yet to be mentioned from the same 
rock at localities further north, I can have no hesitation in 
referring this limestone on Clear Water, and near there on the 
Athabasca river, to the horizon of the Hamilton group proper. 
If we regard this as a settled point, the next question that 
naturally suggests itself, is, to what particular horizon do the 
dark bituminous shales and superincumbent arenaceous de- 
posits of this vicinity belong? Sir John Richardson and Mr. 
Isbister, as already mentioned, referred the former to the 
Marcellus shale. They were led to adopt this conclusion be- 
cause some fossils collected from these beds on the shores of 
Great Bear Lake, by the former of these gentlemen, were 
referred doubtfully by Mr. Woodward, to “ Tentaculites fissur- 
ella IIall, and SProphomena mucronata, S. setigera and Orthis 
limitaris of the same author.” As Strophomena setigera (a 
true Chonetes) and Tentaculites fissurella are also said to occur 
in the Genesee slate, above the Hamilton group, as well as in 
the Marcellus shale below, while it would be impossible to 
distinguish the other two small fossils mentioned by the aid CHICAGO ACADEMY OF SCIENCES. 
65 
of rough wood cuts and more unsatisfactory descriptions, from 
allied species of any age, this palaeontological evidence would 
be far from conclusive, even if not conflicting with other facts. 
When we bear in mind, however, that the Marcellus shale of 
the New York series, holds a position immediately beneath 
the Hamilton beds proper, while the bituminous shales under 
consideration clearly occupy a position above that horizon, it 
must be manifest that they cannot represent the Marcellus 
beds if this formation and the Hamilton strata are developed 
as separate rocks in this region. From all the facts, it is far 
more probable that this Clear Water and Athabasca bitumi- 
nous shale represents the Genesee slate, which everywhere 
holds a position above the horizon of the Hamilton beds.1 
In regard to tlie age of tlie heavy deposits of sandstone and 
less coherent arenaceous material overlying the dark shales 
and limestone in the region of Clear Water river, and at vari- 
ous places farther north on the Athabasca and Mackenzie 
rivers, we unfortunately have no satisfactory information, none 
of the fossils in the collection having been obtained from 
these beds. From their constant association, however, with 
the bituminous shales and limestones, and the fact that similar 
layers of sandstone were at a few places seen alternating with 
the bituminous strata, while these overlying sandy beds are 
themselves often highly charged with bituminous matter, it 
is probable that at least a portion of this arenaceous series 
may also belong to the Devonian epoch, or more properly 
represent the Chemung group of the New York series. Still 
I suspect that in the vicinity of Methy portage, as well as at 
some other places north of there, the upper less coherent part 
1 It may be proper to mention, in this connection, that the dark bituminous shale or 
slate, known as the “Black Slate ” of the Western States, which is rather extensively 
developed in Southern Indiana, and portions of Illinois, Kentucky, Tennessee, and some 
other Western and Southern States, holds exactly the same position with relation to the 
Hamilton beds as the Clear Water and Athabasca shales; which it also resembles in being 
often connected with sulphur, brine, and oil springs. Formerly this black slate was 
supposed to represent the Marcellus shale (see 13th An. Report Regents University, New 
York, p. 96, Jan. 1861), but it was shown by Mr. Worthen and the writer to hold a posi- 
tion above the Hamilton strata, and consequently to be more probably the equivalent of 
the Genesee slate (Am. Jour. Sci., Yol. xxxii, p. 167, Sept. 1861), as has also since been 
suggested by others. (See a supplementary note to the 16th An. Report Regents Uni- 
versity of N. Y., p. 81. dated Sept. 1861). 66 
TRANSACTIONS OF THE 
of these arenaceous deposits may be much more recent, or 
even belong to the Cretaceous or Tertiary epoch, or possibly 
to both. Future explorations must settle these questions. 
As already stated, these sandy strata continue for some 
distance below the mouth of Clear Water river, on the 
Athabasca, surmounting the older deposits, and are at various 
places impregnated with bituminous matter. At one locality 
below an old trading post, named Pierre au Calmut, Sir John 
Richardson says they are so saturated with this mineral that 
fragments become soft and plastic when held in the hand. 
He also states, in regard to this locality, that “the whole 
country, for many miles around, is so full of bitumen that it 
flows readily into a pit dug a few feet below the surface.” 
Other exposures of this sandstone are seen at several places 
between this and Athabasca lake. 
Around the western extremity of Lake Athabasca, granite 
rocks occur along the shore, and form small islands at several 
places between the mouth of Athabasca river and the outlet 
of the lake. Between Athabasca and Great Slave lakes the 
connecting stream takes the name of Slave river, and flows in 
a northwesterly direction. The same granitic rocks occur 
along its shores for some distance down, but at places some 
forty miles below Lake Athabasca, dark, impure limestones 
occur, containing mineral pitch. From one of these beds Sir 
John Franklin collected, in 1825, some fossils referred to 
“aSpvrifer aoutus, and several Terebratulae, resembling T. 
resupinataP Associated with these he also found a “ Cirrus 
and some crinoidal remains.” Spirifer aoutus, however, being 
a carboniferous species, and Terebratula resupinata a Liassic 
form, it is evident there is some error in these indentifications, 
since all the other known facts indicate that these are the 
same Devonian rocks already mentioned. 
None of the specimens before me being from localities on 
Slave river, I can add nothing in regard to the geological 
formations along its course to what has already been pub- 
lished by Sir John Richardson. He mentions several rocky 
rapids and falls along its upper half and the occurrence of 
limestone cliffs, granite, sienite, crystalline limestone, etc., 
forming picturesque scenery. On Salt river, a small stream 67 
CHICAGO ACADEMY OF SCIENCES. 
coming in on the west side, about seventy miles below Slave 
lake, copious brine springs, and a few outcrops of gypsum are 
known to occur. 
The formations in this region Sir John Richardson supposed 
to be Silurian, and as he conjectured, of the Onondaga salt 
group, though he mentions no fossils, and seems to have based 
his opinion mainly on the presence of brine springs. Below 
the mouth of Salt river, he says the banks are alluvial all the 
way down to Slave lake. Near the mouth of the eastern 
branch of Slave river, he saw an island fifty feet in height, 
composed of granite; and adds, “beyond that to the east- 
ward the banks of the lake are wholly primitive.” That is 
to say they belong to the vast azoic area extending along the 
eastern margin of the great Palaeozoic basins of Mackenzie river 
and Lake Winnipeg, to Lake Superior. 
The south shore of Slave lake, from near the mouth of 
Slave river westward to the outlet, seems to be composed 
mainly of dark limestone and bituminous shale, referred by 
Sir John Rigiiardson to the Erie division of the New York 
series. At one locality, thirty-five miles west of Fort Resolu- 
tion, he collected from the shales the fossils already mentioned 
as having been referred, doubtfully, by Mr. Woodward, to 
Tentaculitesfissurella, Strophomena setigera, and Avicula laevis, 
Hall. In the limestones beneath this shale, he collected “a 
Strombodes of Hall (Cysteopliyllum T) having its cysts filled 
with bitumen, and a Favosites very like F. polymorpha of the 
Plymouth marbles.” After examining these fossils, and the 
other specimens collected here, Mr. Woodward adds, “ I have 
not identified any of the Terebratulae from Great Slave lake, 
but they are certainly Devonian or Carboniferous.” 
Mr. Isbister, in speaking of the limestones along tlie "banks 
of Slave river, near its month, remarks that they are “like 
those on Elk (Athabasca) river, highly bituminous,” and 
adds, “but they are chiefly remarkable from their association 
with extensive beds of compact gypsum, in connection with 
extremely copious and rich salt springs. When they ap- 
proach the crystalline rocks they are found, like those of Lake 
Winnipeg, to be highly magnesian,” etc. The fossils which 
he mentions as having been collected “ from this district,” now 68 
TRAXSACTIOXS OF THE 
in the British Museum, are “ Spirifer crispus Dalrn.? Rhyn- 
chonellaphoca Salter, Atrypa laevis Vanuxem, Atrypa reticu- 
laris, an Orthis, two small Spirifers like S. trapezoidalis 
Dalm. and S. pisum Sow., and fragments of an encrinital 
stem.” Unfortunately he does not say at what particular 
locality these fossils were collected, nor whether they came 
from the dark bituminous limestones and shales of this region, 
or from beds beneath them. He colors, however, on his map, 
a patch of Silurian here, extending some sixty or seventy miles 
along the southern shore of Great Slave lake, immediately 
west of the mouth of Slave river, which he refers to the 
horizon of the Onondaga salt group (upper Silurian). 
Although I am not prepared to say that there may not be 
Silurian rocks exposed at some localities within the area 
colored by Mr. Isbister, I fully concur with Sir Johx Richard- 
s'ox and Mr. Woodward in referring the dark bituminous lime- 
stones and shales here to the Devonian system. This opinion 
is not based alone upon the fossils mentioned by Sir John 
Riciiardsox, but in part upon a small collection now before 
me, obtained from these rocks by Mr. Kexxicott, at a locality 
near Fort Resolution. These fossils are contained in a dark, 
impure limestone matrix, so highly charged with bituminous 
matter that it will ignite and blaze for an instant, like bitu- 
minous coal, when thrown into a hot fire. They are Favo- 
sites polymorplia, Atrypa reticularis, a small smooth Spirifer 
{Martin/id), Cyrtina hamiltonensis? a Chonetes marked with 
rather coarse radiating striae, regularly crenated by concen- 
tric markings, and a small Productus, with regular concentric 
wrinkles on the dorsal valve, and fine radiating striae on the 
ventral. Also a minute Lingula, having exactly the outline 
of L. spatulata Hall, but more convex than any specimens 
of that species I have seen, together with the pygidium of a 
Proetus, and imperfect casts of a LucinaX\k.c bivalve. 
From the presence of a Productus amongst these fossils, 
and the affinities of some of the others, particularly when we 
take into consideration the similar bituminous character of 
the matrix to the Hamilton group beds on Clear Water and 
Athabasca rivers already mentioned, I can scarcely doubt 
that these rocks belong to the Devonian system, and probably CHICAGO ACADEMY OF SCIENCES. 
69 
to near the horizon of the Hamilton group. The occurrence 
here of the numerous brine springs mentioned by Mr. Isbis- 
tee, rather confirms this opinion, since saline springs are very 
common in districts underlaid by rocks of this age, not only 
at the various localities already mentioned on the upper 
tributaries of Mackenzie river, but in the region of Winni- 
pigoos, and south-east of there, at various places, even to 
North Red River. Hence if the fossils mentioned by Mr. 
Isbistek have been correctly identified, I think they must 
have been obtained from a lower geological horizon than the 
dark bituminous shales and limestones mentioned. 
From the outlet of Great Slave lake commences Mackenzie 
river proper. Along this stream exposures of dark bitumi- 
nous shale, containing fragments of Tentaculites, are seen at 
several places between the outlet and Fort Simpson, at the 
mouth of Liard river. There are no specimens in the collec- 
tion under consideration from these outcrops of shale, though 
they doubtless belong, as suggested by Sir John Richards ox, 
to the same Devonian series seen along the north shore of 
Great Slave lake, and on Clear Water and Athabasca rivers. 
This suggestion receives some support from a few fossils 
broken by Mr. Kennicott from loose masses of dark bitumi- 
nous limestone along the shores of Liard river near its 
mouth. These are an Orthis I cannot distinguish from O. 
ioivensis of the Hamilton group, a small Martinia apparently 
identical with that mentioned in the rocks near Fort Resolu- 
tion, and a new Spirifer I have described in another part of 
this paper, under the name of 8. Kennicotti. 
Below Fort Simpson, a few high, precipitous Fills, appa- 
rently spurs of the Rocky Mountains, are seen on either side 
back from the river, and nearly horizontal beds of limestone, 
overlaid by dark shales, occur along the shores. Further 
down, an island composed of dark gray bituminous limestone, 
dipping to the southeast, divides the river, and on the right shore 
below this there is a hill called the “Rock by the river’s 
side,” presenting a precipitous front of similar limestone 
strata, rising abruptly from the water’s edge to an elevation 
of near five hundred feet. The strata composing this hill 
are highly inclined to the north-west. Unfortunately no TRANSACTIONS OF THE 
fossils have yet been collected from these rocks at this locality, 
though Mr. McFarlane saw embedded in some of the strata 
large shells, which, judging from his description, probably 
belong to the genus Nautilus or Gyroceras. 
Sir John Richardson saw a thermal saline spring flowing 
from these rocks, and leaving on their surface an incrustation 
of sulphate of lime. At some places here he mentions seeing 
nearly horizontal beds of limestone, overlaid by shale, abutting 
against the upturned older strata composing these elevated 
hills and ridges. 
Between Fort Norman and the mouth of Bear Lake river, 
the Mackenzie enters a Lignite Tertiary formation, apparently 
of the same age as the Great Lignite deposits of the Upper 
Missouri. Its entire thickness is unknown, but it rises from 
beneath the water level to an elevation of one hundred and 
fifty feet or more. Like the Upper Missouri Lignite deposits, 
this formation is composed of beds of sand, pebbles, pipe and 
potter’s clays, etc., with Lignite strata of various extent; some 
beds of the latter being at places as much as eight to ten feet 
in thickness. These Lignites sometimes ignite spontaneously 
and burn for many years, fusing and consolidating the adja- 
cent clays and sand into masses resembling volcanic products. 
This formation has been accurately described by Sir John 
Richardson, who correctly referred it to the Tertiary epoch. 
In his “Journal of a Boat Voyage through Prince Rupert’s 
Land,” he also gives figures and descriptions of several 
species of fossil plants found in these beds, some of which 
are very similar to species found in the Lignite deposits of 
the Upper Missouri. 
In the collections now under consideration, there are speci- 
mens apparently of a Taxites, collected from this formation 
Iby Mr. B. R. Ross, of the Hudson’s Bay Company, near the 
mouth of Great Bear river, which, after comparison with 
specimens brought by Dr. Hayden, from the Lignite forma- 
tions of the Upper Missouri, I can scarcely believe to be 
specifically distinct from the latter. If any shells of mollusks 
occur in these Tertiary beds at this place or further north, it 
would be highly desirable that a good collection of them CHICAGO ACADEMY OF SCIENCES. 
should be obtained for comparison with those of the great 
Lignite deposits of the Upper Missouri region. 
From the statements of Sir Alexander McKenzie, Sir 
John Franklin, Sir John Bichardson, Mr. Isbister, and 
other explorers, as well as of various intelligent gentlemen 
connected with the Hudson’s Bay Company, we have every 
reason to believe that an almost continuous belt of these Lig- 
nite Tertiary deposits extends along the eastern flanks of the 
Bocky Mountains, from the Arctic Ocean southward, so as to 
connect with the Great Lignite Tertiary basin of the Upper 
Missouri. It is jirobable, however, that some of the expo- 
sures of Lignite mentioned by these gentlemen may belong 
to the Cretaceous epoch. 
The area occupied by these Lignite formations at the mouth 
of Bear river must be comparatively narrow where crossed 
by Mackenzie river, since older rocks occur again immedi- 
ately below the mouth of the former stream. The Lignite 
beds, however, are seen at some places farther down, mostly 
on the west side of the Mackenzie and on Peel’s river. They 
seem not to extend, at least for any considerable distance, 
across on the north side of Bear river, east of the Mackenzie, 
several elevated ridges of older strata occupying much of 
that region. One of these, at the mouth of Bear river, rises 
abruptly to an elevation of six or seven hundred feet above 
the water, and seems to be mainly composed of highly in- 
clined, dark, more or less bituminous limestone, apparently 
of the same age as the “ Bock by the river’s side,” already 
mentioned. In 1825, Sir John Franklin saw here “some 
sulphurous springs, and streams of mineral pitch issuing from 
the lower parts of the limestone strata.” 
A similar hill, apparently composed of the same formation, 
occurs near the rapids in Bear river between twenty and thirty 
miles from its mouth, rising from a narrow base to an elevation 
of eight or nine hundred feet above the river. This hill seems 
to be mainly composed of rather thick beds of dark lime- 
stone, which at some places dip to the north-west at an angle 
of 45 degrees. 
At tlie rapids, Bear river passes between nearly perpen- 
dicular walls from ninety to one hundred and twenty-five feet TRANSACTIONS OF THE 
in height, composed below of grayish, undisturbed beds of 
argillo-arenaceous material containing minute particles of 
lignite, and, in concretions, impressions of fern leaves. Over- 
lying this are beds of fine sandstone, with, near the summit, a 
stratum of dolomite, and above all a layer of dark gray lami- 
nated limestone. These sandstones and shales, Sir John 
Richardson says, have much the appearance of the coal meas- 
ures, but as he found at the base of the exposure, in some 
loose pieces of brown ferruginous sandstone, specimens of an 
Ammonite, and as two species of that genus have since been 
described from that neighborhood by the writer, in Prof. 
Hind’s Report on the Assiniboine and Saskatchewan Expl. 
Expedition, while there are from near there, in the collection 
under consideration, fragments of an Ammonite and an Ino- 
ceramus, it is highly probable that these strata belong to the 
Cretaceous system, though some of the ujiper portions may 
be of Tertiary age. The fact that these strata lie in a hori- 
zontal position so near hills of highly inclined limestones, 
probably of Devonian age, evidently shows that they belong 
to some of the more modern epochs. Undisturbed strata 
apparently of the same shale and sandstones continue along 
Bear River to its source in Great Bear lake, and around the 
shores of the latter. 
On Mackenzie river, below the mouth of Bear river, ex- 
posures of dark bituminous shale are seen at several places; 
and at a locality about forty-five miles below Bear river, it 
forms perpendicular cliffs very similar to the outcrops seen on 
Clear Water and Athabasca surmounting the limestones con- 
taining Hamilton group fossils. Still farther down, walls of 
gray argillaceous sandstone, in nearly horizontal layers, con- 
tinue for many miles along the shores. At the rapids farther 
down, abrupt hills of highly inclined strata of dark grayish 
limestones similar to those forming the hills and ridges in the 
vicinity of Bear river occur. 
Below tlie rapids, horizontal beds of sandstone are again 
seen, and at a locality some forty miles below the rapids, 
called the “Ramparts,” lat. 66 deg., long. 127 deg., the river is 
walled in on either side between nearly perpendicular preci- 
pices, fifty to two hundred feet in height, consisting of highly CHICAGO ACADEMY OE SCIENCES. 
73 
inclined strata of limestone very similar to those seen in the 
hills near Bear lake. These beds are often impregnated with 
bituminous matter, and generally dip at a high angle in a 
northwesterly direction. Near the middle of this defile, Sir 
John Richardson collected from these rocks some fossils 
referred by Mr. Sowerby to “ Terebratula sphaeroidalis, Pro- 
ducti, a coral of the genus Amplexus, Terebratula resupinata, 
Spirifer acutus, a Cirrus and some crinoidal remains.” 
Sir John Richardson expresses no opinion in regard to 
the age of the rocks at the “Ramparts,” further than to say 
they are very similar to those se£n in the other high hills and 
ridges further up the river. Mr. Isbister refers them to 
the Carboniferous system. That this is an error, however, I 
can scarcely entertain a doubt, since it is manifest some mis- 
take must have been made in these identifications,—Terebratula 
sphaeroidalis and T. resupinata being Jurassic species, and 
Spirifer acutus a Carboniferous species. I suspect, however, 
that the shell here and elsewhere mentioned by him as Tere- 
bratula resupinata, is the Orthis I have referred to O. iowensis, 
since it nearly resembles Orthis resupinata (which it will be 
remembered was described by Sowerby as a Terebratula), or 
another similar species I have described from a locality farther 
down the river under the name O. McFarlanei. 
I am led to this conclusion from a careful examination of 
some fossils collected by Mr. Kennicott, at the “Ramparts,” 
and others by Mr. McFarlane from the same formation, forty 
miles below. Those from the “ Ramparts ” consist of a coral 
having the external appearance of Amplexus, but differing in 
its internal structure, Favosites polyrnorpha, a massive species 
of Alveolites, a Zaphrentis (Z. recta of this paper), Atrypa 
reticularis, A. aspera, a Rensselaeria? Gyrtina hamiltonensis, 
and a small Spirifer (Martinia). From this assemblage of 
fossils, I am clearly convinced that these rocks cannot belong 
to the Carboniferous system, but that they are Devonian, and 
most probably belong to about the horizon of the Hamilton 
group. 
At numerous places below the “Ramparts,” particularly 
between these and the site of old Fort Good Hope, long, nearly 
perpendicular bluffs, composed of limestone, sandstone and transactions of the 
bituminous shales occur, sometimes more than one hundred 
and sixty or seventy feet in height. These beds are usually 
nearly horizontal, and at some places the bituminous shales 
alternate with the limestones, while both are overlaid by the 
sandstones. From the limestones, at one place, thirty miles 
below the “ Ramparts,” Sir John Franklin collected speci- 
mens which Sir John Richardson says are “full of shells, 
many of which are identical with those of the flat limestone 
strata of the Athabasca river.” At another locality ten miles 
below this, Mr. McFarlane collected from these lime- 
stones some of the same corals obtained by Mr. Kennicott 
at the “Ramparts,” also Atrypa reticularis (large variety), an 
undetermined ffliynchonella, Orthis McFarlanei, described in 
this paper, a large Spirifer (Martinia), which I have called 
S. FranJclinii, and a large Gyroceras I have described under 
the name of G. Logani. 
There are, likewise, in the collection from this locality, 
fbund in loose masses, casts of a Rensselaeria a little under 
the usual size of the well known if. ovoides of the New York 
Oriskany sandstone, from which it differs specifically. This 
fossil is quite abundant, and occurs in a different matrix from 
that of the other species obtained here, being in a rough, very 
hard, yellowish-gray rock, looking much like a compact silicious 
sandstone, but when examined under a magnifier, it is seen to 
be a fine-grained subcrystalline dolomite. 
From the other fossils obtained at these outcrops, they 
would seem to belong to the same rock as that forming the 
“ Ramparts,” which, as previously remarked, is probably of 
about the age of the Hamilton Group. These limestones 
appear to have also a considerable east and west extension 
near this latitude, since Mr. Isbister, in speaking of the form- 
ation at the “Ramparts” above here, says, “it is continued in 
a westerly direction to the Rocky Mountains, the lower eleva- 
tions of which are composed of it at that portion of the range 
through which Peel’s river takes its course.” 
A few fossils in the collections under examination, found by 
the Rev. Mr. W. W. Kirby along Porcupine river, west of the 
Rocky Mountains, also indicate the continuation or reappear- 
ance of these rocks on the western slopes of this range, and their CHICAGO ACADEMY OF SCIENCES. 
75 
probable extension further westward into Russian America. 
The fossils here alluded to are Favosites polymorplia, appa- 
rently two or three species of undetermined turbinate corals, 
an aggregated Cyathophyllum, a Palaeocyclus, Atrypa aspera, 
and Cyrtina hamiltonensis. 
Hamilton group fossils were likewise collected by Mr. 
McFarlane east of Mackenzie river, at localities on Anderson 
river,2 about one hundred and fifty miles in a north-eastward 
direction from the “Ramparts.” These are Favosites poly- 
morplia, Qysteophyllum americanumf several undetermined 
turbinate and cylindrical corals, some of which appear to be 
identical with species found at the “ Ramparts,” a new species 
of Smithia (S. Verrilli of this paper), crinoidal columns, Orthis 
McFarland, Atrypa reticularis (large dilated variety), A. 
aspera, Cyrtina hamiltonensis, or a very closely allied species, 
Pentamerus borealis (of this paper), and a smooth Pensselaeria? 
apparently identical with the casts found forty miles below 
the “Ramparts.” 
About one hundred and fifty miles below the “Ramparts,” 
or some sixty miles below the site of old Fort Good Hope, 
precipitous rocky bluffs, from fifty to one hundred feet in 
height, occur on both sides of Mackenzie river, forming what 
is known as the “ Narrows.” In the collections under exami- 
nation there are no specimens from this locality, but Sir Johist 
Richardson describes the “Narrows” as “a defile similar to 
that of the 4Ramparts.’” He also states that the cliffs here 
are mostly sandstone, in nearly horizontal strata, which at 
some places incline slightly to the south-east. Some of the 
beds are rather compact and contain much calcareous matter, 
while others are shaly and strongly impregnated with alum. 
These alum shale beds extend for some distance up Peel’s 
river, a small stream entering the delta of Mackenzie river on 
the west, and also around the east and west sides of the delta, 
as well as along the sea coast at places. 
The delta of Mackenzie river, which commences some 
twenty miles below the “Narrows,” is about ninety miles in 
length, north and south, and widens gradually northward 
2 Anderson, or Begh-ula-tesse river, is a small stream flowing northward into the 
Arctic sea. TRANSACTIONS OF THE 
from its head to the shores of the Arctic sea, where it is 
between forty and fifty miles in breadth. This whole area is 
occupied by numerous low islands, more or less overgrown 
with trees, and separated by the several channels of the river. 
On the west it is bounded by an elevated district connected 
with spurs of the Rocky Mountains, and on the east by what 
are known as the “Reindeer hills,” from 400 to 800 feet in 
height, forming, as is supposed, a continuation of the range 
seen at the “Narrows.” At some places, about twenty miles 
below the head of the delta, outcrops of dark, bluish-gray 
limestone are seen along the base of these hills, and at other 
places further down, some high exposures occur, composed of 
strata of slaty clay above, sandstone in the middle, and bluish- 
gray alum shale at the base. 
In regard to the age of this alum shale formation in the 
region of the delta of Mackenzie river, we have no reliable 
information, no organic remains having been found in it, so far 
as known to the writer. From Sir John Richardson’s de- 
scriptions, I infer that it differs in some respects from the very 
dark bituminous shales found associated with the Devonian 
rocks on the upper part of Mackenzie river and its tributaries; 
and as some similar beds occur about the western extremity of 
Great Bear lake, in the region of Tertiary and possibly Creta- 
ceous rocks, while Lignite deposits are found on some of the 
islands near the mouth of Mackenzie river, and at other places 
on the main land, in the region of the delta, I infer that this 
formation most probably belongs to the Tertiary or Cretaceous 
system. 
From the foregoing remarks, it will be observed that 
amongst all the collections under examination from various 
localities along Mackenzie river and its tributaries, between 
Clear Water river and the Arctic ocean, a distance by the 
general course of the valleys of more than one thousand miles, 
there are no Carboniferous or characteristic Silurian forms. It 
would, however, be rash to conclude from this that no rocks 
belonging to either of these epochs are anywhere exposed 
along these streams. Yet the impression left upon the mind 
of the writer from examining these collections, and from read- 
ing Sir John Richardson’s notes, as well as from all he has CHICAGO ACADEMY OF SCIENCES. 
been able to learn from Mr. Kennicott, is, that no Carbon- 
iferous rocks crop out along these streams between Clear 
Water and the mouth of Mackenzie river. It is, nevertheless, 
highly probable that they, as well as Silurian strata, exist in 
the Rocky mountains west of these rivers. It is also probable 
that Silurian rocks occur at places on Slave lake, east of the 
mouth of Slave river, and on Great Bear Lake, as represented 
on Mr. Isbistee’s map, as well as on Slave river, and at other 
places between the great azoic area on the east and the belt of 
Devonian rocks extending along the valley of Mackenzie river 
and its tributaries. 
It is an interesting fact, in connection with the Devonian 
deposits of Mackenzie river, that the same rocks appear again 
in a belt of country west of Lake Winnipeg, extending thence 
southward and south-eastward through Dakota, Minnesota 
and Iowa, to Hock Island, Illinois. By consulting Aeeow- 
smith’s general map of British America, in connection with 
Isbistek’s and Prof. Hind’s geological maps of portions of the 
same, and Sir William Logan’s recently published beautiful 
geological map of the Canadas, the Saskatchewan country, 
and northern portions of the United States, it will be seen 
that the belt of Hamilton group rocks laid down by the last 
mentioned authors, as extending from Rock Island, Illinois, in 
a north-westerly direction to the Saskatchewan, ranges very 
nearly in the same direction, and almost on a line with the 
general trend of the great valley of Mackenzie river and its 
upper tributaries. From all the facts, therefore, now known, 
it is highly probable that there is a continuous stretch of 
Devonian rocks, mainly of the age of the Hamilton group, 
extending from Rock Island, Illinois, in a north-westerly direc- 
tion to the Arctic ocean, a distance, in a right line, of near 
two thousand five hundred geographical miles. 
It is also worthy of note, that collections of fossils now be- 
fore me, obtained at about the extreme opposite ends of this 
long belt of Devonian rocks, and hence at localities separated 
by nearly thirty degrees of latitude, include a considerable 
proportion of undoubtedly identical species, and altogether 
present a degree of general similarity strongly corroborating 
the generally accepted opinion that climatic conditions, if not 78 
TRANSACTION'S OF THE 
uniform over the whole world, were at least little if at all 
influenced by difference of latitude during the Palaeozoic 
epochs. 
Supplementary Note. 
Before commencing the descriptions of the fossils in the col- 
lection under investigation, I would call the attention of the 
intelligent gentlemen connected with the Hudson’s Bay Com- 
pany, as well as of others more directly interested in the 
establishment of settlements in these remote northern districts, 
to the numerous indications of extensive deposits of petroleum 
along the valley of Mackenzie river and several of its tribu- 
taries, particularly on the Athabasca river. It is true, these 
localities are too distant from markets to attract the attention 
of speculators, but it will be readily understood that an 
abundant supply of rock oil here would be of great value to 
the employees of the Fur Company, wdio, I was informed by 
Governor McTavisii, now transport all they consume of this 
useful article, by long overland journeys and boat voyages 
from the south, to their various stations scattered throughout 
the vast area of their operations. In addition to this, should 
settlements ever be established in the region of Athabasca 
river, or Bear lake, we could scarcely overestimate the value 
and importance that a few flowing oil wells would be to the 
inhabitants of these districts, since such wells might not only 
afford a sufficient supply of oil for illuminating purposes, but 
even be used as a concentrated fuel for cooking, warming 
houses, and driving steam engines, and thus measurably com- 
pensate for the scarcity of wood in this rigorous climate. 
That large quantities of oil exist at no very great depths 
beneath the surface at some of the various localities already 
mentioned, where the rocks and earth are saturated with 
pitch, is highly probable;—the pitch being merely the fixed 
residue left by the evaporation of the volatile portions of 
petroleum that found its way to the surface during the long 
ages of the past. The significance of the oil indications 
alluded to here will be more apparent, when it is remem- 
bered that the rocks, where they occur on Athabasca river CHICAGO ACADEMY OF SCIENCES. 
and other localities mentioned, belong to about the same geo- 
logical horizon as that in which the oil of many of the great 
flowing wells of Pennsylvania is supposed to have its origin. 
The occurrence of numerous copious brine springs here is also 
worthy of note. 
Descriptions of the Fossils contained in the Collection. 
CORALS.3 
Genus Ci/atJlophyllum Goldfuss, 1826. 
Cyathophyllum, arcticum Meek. 
Family CYATIIOPHYLLIDAE. 
Pl. XI, fig. 8. 
Corallum compound, aggregated or growing in masses two or three 
inches in diameter, from a base composed of a single corallite, increas- 
ing by lateral and interstitial budding. Corallites very unequal in size, 
generally crowded together and angular, but apparently sometimes 
scarcely in contact, and rounded. Epitheca well developed and dis- 
tinctly wrinkled on the outer or under side of the corallum, and around 
each corallite, when they are not crowded together. Calices, like the 
corallites, varying much in size and form, rather deep, with nearly 
vertical sides. Septal radii eighteen to about twenty-two, thin, and 
alternating with the same number of very short rudimentary secondary 
ones, which usually merely form rather prominent striae on the walls 
between the others; principal series extending to the middle of the 
calices, but rarely reaching quite to the middle of the corallites, as seen 
in the transverse section. Tabulae very thin, somewhat irregular, and 
apparently occupying a considerable portion of the middle of each 
corallite, nearly transverse, but curving up on each side, as seen in longi- 
tudinal sections; dissepiments forming very small vesicles, arranged in 
oblique ascending series, in a thin sui’rounding zone. 
Height of corallum, 1.70 inches; greatest breadth at summit, 2.70 
inches. Diameter of calices varying from 0.14 to 0.36 inch; average 
depth about 0.18 inch. 
In its general appearance, tliis coral resembles Cyatho- 
phyllum quadrigeminum of Goldfuss, as figured on pi. xviii, fig. 
3 I am under obligations to Prof. A. E. Verrill, of Yale College, wlio has devoted 
especial attention to the study of recent fossil corals, for suggestions in regard to the 
generic relations of several of the corals described in this paper, respecting which I was 
in doubt. 80 
TRANSACTION’S OF THE 
6, b, of Ms Petrefacta Germaniae, more nearly than any other 
species with which I am acquainted, but differs materially 
in apparently always increasing by interstitial and lateral 
gemmation, as well as in the smaller number and unequal 
development of its septal radii. 
The specimen figured does not show the loose mode of 
growth and rounded character of the corallites seen in other 
individuals too large to be conveniently figured. 
Locality. Porcupine river, Russian America, lat. 66 deg. 
27 min. 1ST., long. 143 deg. W. Also on Grand river, and near 
Fort Good Hope on Mackenzie river, lat. 66 deg. N., long. 
128 deg. W. 
Germs Cysteophyllum Lonsdale, 1839. 
Cysteophyllum americanum, var. arcticum Meek. 
PL XI, fig. 6. 
Cystipliyllum americanum Edwards & Haime, Monogr. Polyp. Foss. (1851), p. 464, 
pi. xiii., fig. 4, 4a. 
Corallum conical, or possibly becoming cylindrical in large specimens, 
straight or somewhat curved. Surface with a thin epitheca, and distinct 
wrinkles, with stronger encircling ridges of growth. Calice circular, or a 
little oval, conical, and of moderate depth; marked with radiating im- 
pressed lines, indicating the position of rudimentary septa, formed by the 
crowding together of the walls of the vesicles within. Interior, as seen 
in a longitudinal section, entirely occupied by a dense vesicular tissue, 
the vesicles being lai’gest and most irregular in the central region, and 
becoming very small, crowded, and arranged in oblique ascending series 
on each side; in a transverse section, showing thin radiating false septa, 
of which about one hundred may be counted in the entire series. 
Near the middle, these false septa are distinct, but they become gradually 
more irregular and obscure as they approach the exterior. 
Length, 2.10 inches, or more ; breadth, 1.25 inches. 
It is witli considerable doubt that I have ventured to refer 
this to the New York species described by Edwards and 
IIaime. Yet it agrees so nearly in its internal structure 
with the figure of that species given by those authors that I 
am led to think it may possibly be the same. It is shorter, 
however, in porportion to length, than a specimen of C. 
ameiicanum, with which I have compared it, while the vesi- CHICAGO ACADEMY OF SCIENCES. 
81 
cles of its interion are proportionally smaller, more crowded, 
and hence more numerous than in the New York species. 
It may be an entirely distinct species, but without more speci- 
mens for comparison, it seems scarcely possible to settle this 
question satisfactorily. 
Locality and position. Onion river, lat. 67 deg. N., long. 
125 deg. W. Collected by K. W. McFarlane. 
Genus Aulophyllum Edwards & IIaime, 1850. 
Aulophyllum ? Richardsoni Meek. 
PI. XI, fig. 3. 
Corallum nearly cylindrical, or in immature examples conical, more or 
less flexuous, and with encircling ridges and wrinkles of growth well 
defined. Epitheca very thin, usually worn off in weathered specimens. 
Calice apparently very shallow and circular, or a little oval. Septa very 
thin, about seventy, of which every alternate one extends to the central 
region, while the intermediate ones all terminate at a kind of rudimentary 
wall, about one-third of the way in from the surface to the middle. 
Space within the inner wall, between the septa, divided into numerous 
small vesicles; intercostal spaces of the outer zone, between the inner 
wall and the surface, occupied by much smaller vesicles, ranging 
obliquely outward and upward. 
I know this coral only from fragments less than 0.80 inch 
in diameter, none of which show the entire length. They are 
also nearly all considerably compressed, but this seems to be 
from accidental pressure. The generic characters cannot be 
made out with much confidence from such materials, and 
hence I am by no means satisfied that the species should not 
be called Cyathophyllum JRichardsoni. As near as its internal 
structure can be determined, however, from the specimens col- 
lected, it would seem to differ from that genus in having an 
inner wall encircling the central region, and thus more nearly 
approaching the genus Aulophyllum. It also wants the 
transverse tabulae generally more or less developed in the 
central region of Cyathophyllum. 
In most of the specimens the epitheca has been removed, so 
as to show the septa very distinctly. Usually about seven of 
these can be counted in a space of 0.20 inch. Where the 82 
TRANSACTIONS OF THE 
epitheca is not removed, however, there seems to have "been 
moderately distinct septal costae marking the positions of 
the septa. The dissepiments are likewise quite distinctly seen 
between the costae of weathered specimens. 
This is almost certainly the coral referred by Mr. Sowekby, 
in Sir John Richardson’s collection, to Ampleocus, which it 
much resembles externally, though it differs widely from that 
genus in internal structure. . 
Named in honor of Sir John Richardson. 
Locality and position. Mackenzie river, at the “ Ramparts,” 
lat. 66 deg., long. 127 deg. 
Genus Zaphventis Rafinesqtte, 1820. 
Zaphrentis recta Meek. 
PL XI, fig. 1. 
Corallum obconical, straight, or probably sometimes a little curved, 
rather attenuate at the lower extremity. Epitheca thick, strongly 
wrinkled, or, at irregular intervals, even constricted by the marks of 
growth, almost entirely concealing the septa. Calice circular, conical, 
and rather shallow; septal fossette lateral,very shallow. Septa thin and 
numbering in the primary series about forty, which alternate with as 
many imperfectly developed secondary ones; on grinding away the 
epitheca, about seven of these two sets may be counted in the space of 
0.20 inch. Tabulae forming irregular vesicular cavities, apparently not 
very distinct from those formed by the dissepiments, excepting that they 
are larger and more transverse. Vesicles of the outer zone rather small 
and ranging obliquely outward and upward. 
Length, 1.70 inches; breadth, 0.95 inch; depth of calice, 0.33 inch. 
Tlie septal fossette is so faintly marked in this species tliat 
it might be readily overlooked, and cause tlie coral to be 
referred to Cyathophyllum. The presence of the fossette, 
however, is obvious enough, when once the attention is drawn 
to it, and warrants the reference of the species, when taken in 
connection with its other characters, to the genus Zaphrentis. 
I am not acquainted with any very closely allied species. 
Locality and position. Anderson’s river, lat. 67 deg. 1ST., 
long. 125 deg. W., and on Porcupine river? lat. 67 deg. 27 
min. N., long. 143 deg. W. Collected by R. W. McFar- 
lane. CHICAGO ACADEMY OF SCIENCES. 
83 
Zaphrentis Mcfcirlanei Meek. 
PI. XI, fig. 2. 
Corallum about medium size, or rather less, conical, and distinctly 
arched, surface with strong irregidar ridges of growth, and, especially 
where the epitheca is a little worn, showing the septa; calice circular, 
oblique, and apparently of moderate depth; septal fossette small, but 
deep and well defined, placed about half way between the middle and 
the side, in a lateral position with relation to the curve. Septa about 
forty, every alternate one being stouter and more prominent than the 
others, and extending to the middle of the calice, where they are con- 
siderably contorted. Tabulae apparently nearly wanting, or only dividing 
some portions of the centro-lateral region into irregular vesicular cavi- 
ties ; outer interseptal area occupied by numerous small vesicles. 
Length, about 2.30 inches ; greatest breadth, 1.20 inches. 
The only specimens of this coral in the collection are con- 
siderably worn, so as to make the surface appear smoother 
than is natural, and remove the margins of the calice in such a 
manner as to make it appear shallow. So far as I have been 
able to make comparisons, it seems to be distinct from the 
described species. 
The specific name is given in honor of Mr. R. W. McFar- 
lane, who discovered and collected the specimens described. 
Locality and position, same as last. 
Genus Smithia Edwards & Haime, 1851. 
Smdthia Verrilli Meek, 
PI. XI, fig. 7. 
Corallum depressed, moderately convex below, where it seems to have 
been protected by a thin epitheca, and attached by a small central 
peduncle ; upper side nearly flat. Calices nearly as deep as wide, with 
vertical walls, and subangular, slightly raised margins, showing about 
fifteen principal septal radii, and as many short intermediate secondary 
ones; the former rather prominent on the walls, and continued in the 
bottom of the calices to the center, while the latter assume the appear- 
ance of raised striae between. Mural circles, as seen in sections, not 
very distinctly defined, being mainly indicated by the sudden thickening 
of the radii as they pass on; situated regularly at intervals of once to 
twice their own diameter apart. Radii thirty to thirty-five, rather thin, 84 
TRANSACTIONS OE THE 
and minutely and very obscurely granulose, or striate on the sides; a 
few of them straighter and more confluent in one direction than the 
others, and generally meeting those from the adjacent corallites at 
various angles, as seen in transverse sections; the twelve to fifteen princi- 
pal ones continued to the center of the mural circles seem to be some- 
times a little twisted about the center, while the others coalesce with 
them, or die out a short distance within the walls. Dissepiments very 
thin, and arching a little downwards, in crossing the intercostal spaces, 
arranged closer together than the radii themselves. 
Transverse diameter of the corallum, 2.20 inches; height of do., 0.75 
inch; breadth of mural circles and calices, 0.13 inch; interspaces from 
0.13 to (occasionally) 0.18 inch. 
In transverse and longitudinal sections tlie radii of tliis 
species are very distinctly visible, but tlie dissepiments, 
wliicb are much thinner, are with difficulty seen in sections, 
though distinct enough on weathered surfaces. Specifically 
it seems fo be most nearly allied to P. Verneuili of Edwards 
&, Haime, but differs in having its mural circles much more 
regularly and closely arranged, while it is more compact in 
structure, not being disposed to separate into flattened 
laminae. 
I take pleasure in dedicating this species to Prof. A. E. 
Verrill, of Yale College, New Haven, to whom I am indebted 
for suggestions in regard to the affinities of the corals 
described in this paper. 
Locality. Anderson river, lat. 67 deg. N., long. 126 deg. W. 
Genus Combophyllimi Edwards & IIaime, 1858. 
Combophyllum multiradiatum Meek. 
PI. XI, fig. 4. 
Corallum depressed, discoid, circular, flat below; upper side with a 
broad, very shallow calice, which is flattened within; septal fossette 
narrow, but well defined, extending from the middle to the margin 
of the calice. Lateral margins rounded, and as it were duplicated 
by a distinct furrow, extending entirely around. Radial septa num- 
bering 48 to 50 in the primary series, which alternate with a shorter 
intermediate series, only extending into the inner margin of the very 
shallow calice. 
Height, 0.13 inch; breadth, 0.67 inch. CHICAGO ACADEMY OF SCIENCES. 
85 
The only specimen of this interesting coral, in the collec- 
tion, is much worn, as if it had been transported by running 
water; consequently it is impossible to determine whether 
the septal radii were crenate or not, though they appear to 
be smooth. It differs widely from the only other described 
species of the genus with which I am acquainted (C1 osirnio- 
rum and C. leonense E. & H.), in its much more numerous 
septa aud more depressed form. 
Although this genus is usually placed in the subfamily 
Zaphrentinae, it certainly differs very materially from the 
other genera of that group. 
Locality. Onion river, lat. 67 deg., long. 125 deg. Col- 
lected by R. W, McFarlane. 
Family FUNGIDAE. 
Genus Paldeocyclus Edwards & IIaime, 1849. 
Palaeocyclus Kirbyi Meek. 
PI. XI, fig. 5. 
Corallum depressed, discoid, circular. Under side perfectly flat, and 
protected by a well-developed, concentrically wrinkled epitheca, with 
some appearance of a small central scar of attachment. Upper side 
with a very shallow central depression or concavity, surrounded by a 
broad, low, rounded rim, formed by the slight projection of the septal 
radii. Columella, if any exists, very short. Septal radii about forty- 
five, in the principal series, with as many shorter intermediate ones ; all 
with margins apparently nearly smooth. 
Height, 0.35 inch; breadth, 1.16 inches. 
In tlie number of its septa, as well as in its general aspect, 
tliis species seems to be related to P. propita Linn, (sp.), but 
it is more flattened below, while its septa show none of the 
distinct crennlations so characteristic of that species. 
Named in honor of Kev. W. W. Kirby, to whom we are 
indebted for the typical specimen, and other Devonian (Ham- 
ilton group) fossils from Russian America. 
Locality. Porcupine river, Russian America, lat. 66 deg. 
27 min. N., long. 143 deg. W. 86 
TRANSACTIONS OF THE 
Family FAVOSITIDAE.4 
Genus FdVOSiteS Lamarck, 1816. 
Favosites polymorpha Goldfuss. (sp.) 
PI. XI, fig. 10. 
The specimens of this species in the collection all belong to 
the slender, branching variety, with the walls thickened, so 
as to give the cells or calices a nearly or quite circular form. 
The branches vary from 0.25 to 0.70 inch in diameter, and 
although found at various localities, the specimens obtained 
are mere fragments, generally in a bad state of preservation. 
According to Edwards & Haime, this is but a mere variety 
of F. cervicomis, of Blainville, which is not improbable. If 
so, the latter name will have to be used for the species, as it 
has priority of date. 
Localities. The specimen figured is from Anderson river, 
lat. 67 deg. N., long. 125 deg. W. Othejr specimens in the 
collection are from near Fort Resolution, on Slave lake, and 
from Mackenzie river, at the “ Rampartsalso, from Porcu- 
pine river, Russian America, lat. 66 deg. 27 min. N., long. 
145 deg. W. 
Genus Alveolites Lamarck, 1801. 
Alveolites vallorum Meek. 
PI. XI, fig. 9. 
Corallum massive, large, wider than high, apparently lenticular in 
form, or sometimes concave below, and convex above ; laminated struc- 
ture not always distinct. Calices very small, or rarely more than 0.03 
inch wide and half that in height, oblique, generally nearly twice as 
wide as high, and more or less rhombic in outline. Walls between the 
calices apparently nearly as thick in worn or weathered specimens, as the 
diameters of the calices themselves. 
Entire size of corallum unknown, apparently sometimes as much as 
four or five inches broad, and one and a half inches thick or high. 
* Prof. Agassiz has shown that the animals of the genus Millepora, previously con- 
sidered true Polypi, have the structure of the Hydroid Acalephs; and from analogy he 
infers that the fossil genera Favosites, Chaetetes, and indeed all of those extinct corals 
belonging to the group Tabulata, were probably formed by Hydroid Acalephs. CHICAGO ACADEMY OF SCIENCES. 
This is probably an undescribed species, although I cannot 
clearly satisfy myself that it is distinct from some of those of 
which I have only seen descriptions without figures. 
Locality. 11 Ramparts,” on Mackenzie river, forty miles 
above old Fort Good Hope. 
BRACIIIOPODA. 
Family LINGULIDAE. 
Genus IAnguld Bruguiere. 
Lingula minuta Meek. 
PI. XIII, fig. 1. 
Shell minute, extremely thin, ovate, rather convex; front rather nar- 
rowly rounded; sides most convex in outline slightly in front of the 
middle, thence narrowing with slight convexity to the beak, which is 
obtusely pointed. Surface polished, but showing, under a strong mag- 
nifier, microscopic lines of growth. 
Length, 0.06 inch, breadth, 0.05 inch. 
This is the smallest specimen of Lingula I have ever seen, 
and may possibly be a young shell. It resembles closely 
Lingula spatula Hall, from the Genesee slate of New York, 
but is rather wider in proportion to length, and has a more 
pointed beak. It is also more convex than any specimens I 
have seen of that species. 
Locality. Near Fort Resolution, on Great Slave lake 
Family STROPHOMENIDAE. 
Genus Strophomena Kafinesque. 
Strophomena (Strophodonta) demissa Conrad. 
PI. XIII, fig. 6. 
Strophomena demissa Conrad, Jour. Acad. Hat. Sci. Philad., Yol. YHI (1842), p. 258, 
pi. xiv, fig. 14; Billings, Devonian Fossils of Canada West (1861), p. 17. 
Strophodorita demissa Hall, Report Regents University, H. T. (1856), p. 131; Iowa 
Report, Yol. I (1858), Part 2nd, p. 495, pi. iii, fig. 5, a—k. 
Numerous fine specimens of this sliell in the collection agree 
exactly in all respects with examples of 8. demissa from the 88 
TRANSACTIONS OF THE 
Hamilton group in Hew York, Iowa, and Illinois. Like the 
latter, they vary considerably in the length of the hinge line, 
which is in some specimens longer than the breadth of the 
valves, and in others shorter, while there are various interme- 
diate gradations in this character. 
Length, 1.17 inches; breadth, 1.37 inches; convexity, 0.44 
inch. 
Locality and position. Clear Water river; Devonian sys- 
tem, (Hamilton group.) 
Strophomena (Strophodonta) subdemissa Hall. 
PI. XIII, fig. 7. 
Strophomena (Strophodonta) subdemissa Hall, 10th Report Regents University, N. Y. 
(1856), p. 145. 
As near as can be determined from a description alone, 
without a figure, this form agrees well with the above type. 
I doubt, however, whether it is more than a variety of S. 
demissa, from the typical form of which it differs only in its 
greater convexity, shorter hinge, and proportionally wider 
area. If these characters were constant, they would of course 
be sufficiently distinct to warrant its separation without doubt, 
but there are so many intermediate gradations as to leave 
some uncertainty in regard to the propriety of separating 
these forms as two distinct species. 
Length, 1.10 inches; breadth, 1.05 inches; convexity, 0.54 
inch. 
Locality and position. Same as last. 
Genus Orthis Dalman, 1828. 
Orthis McFarland Meek. 
PL XII, fig. 1. 
Shell sub cord ate, resupinate, very gibbons ; length (in adult examples) 
greater than the breadth ; cardinal and umbonal regions very narrow ; 
postero-lateral margins straight, and rapidly diverging forward to the 
widest part of the valves, which is a little in advance of the middle; 
hinge line short, or scarcely equaling half the greatest breadth of the 
valves; cardinal area moderate, nearly twice as high in the ventral 
valve as in the other, strongly arched in the dorsal valve, and slightly CHICAGO ACADEMY OE SCIENCES. 
89 
in the ventral, where it is less than half as high as wide, and ranges 
nearly at right angles to the plane of the valves; foramen triangular, 
and about two-thirds as wide as high. Smaller or ventral valve convex 
in the latei*al and umbonal regions, the most gibbous part being near the 
beak, which is short and a little incurved at the point; provided with a 
broad rounded mesial sinus, which commences very shallow near the 
middle of the valve, and widens and deepens rather rapidly towards 
the front margin to which it imparts a broadly emarginate outline. 
Larger or dorsal valve extremely gibbous, particularly in the region of 
the umbo, which, in adult specimens, projects considerably beyond that 
of the other, and is at all ages strongly incurved. Surface marked with 
fine radiating striae, some nine or ten of which may be counted in the 
space of 0.10 inch. 
Breadth of an adult, 1.50 inches; length from the most prominent 
part of the umbo of the ventral valve to the front, 1.60 inches. Greatest 
convexity of the two valves, 1.16 inches; length of hinge, 0.77 inch. 
This fine OrtMs will be readily distinguished from all the 
known species of the genus by its peculiar form alone. Its 
most marked characters are the shortness of its hinge, the 
great convexity of its dorsal valve, and the narrowness of the 
umbonal region of both valves. These peculiarities, together 
with the remarkable gibbosity and prominence of the umbo 
of its dorsal valve give it much the general form of JPenta- 
merus galeatus. This peculiar form is not abnormal, there 
being five specimens in the collection, all of which agree 
exactly in their general outline. The specimens being all 
more or less worn, do not show very distinctly the surface 
striae, though they seem to bifurcate so as to preserve the 
same size on all parts of the valves. Under a magnifier, the 
worn and exfoliated surfaces show very distinctly the numer- 
ous minute punctures, and occasional larger openings in the 
striae so often seen in shells of this genus. The muscular 
scars of the interior, so far as can be determined from internal 
casts, seem to be much like those of a variety of 0. iowensis, 
and analogous species 'of this genus from the Devonian and 
Carboniferous rocks. 
I have named tbis interesting species in honor of Mr. R,. W. 
McFaelane, of the Hudson’s Bay Company, to whom we are 
indebted for the specimens of this and many other species of 
Devonian fossils from these distant northern regions. 
Locality and position. Forty miles below Fort Good Hope, 90 
TRANSACTIONS OF THE 
on Mackenzie river, and on Lockhart river, lat. 6? deg. 15 
min. N., long. 126 deg. W., in tlie Devonian, (Hamilton group.) 
I have also seen specimens wliicb I believe to belong to this 
species from tlie Hamilton group beds of Iowa and Illinois. 
Orthis ioicensis Hall? 
PI. XII, fig. 2, 
Orlhis ioicensis Hall, Iowa Report, I, Part 2nd (1858), p. 488, pi. xi, fig. 4; Billings 
in Hind’s Report Expl. Assiniboine, Saskatchewan, etc. (1859), p. 193. 
Shell large, robust, resupinate, suborbicular, or in adult examples, a 
little wider than long, and more or less emarginate in front; rather com- 
pressed in young specimens, but becoming gibbous with age. Ventral 
valve much less convex than the other, its greatest convexity being at 
the umbo, while its anterior margin in mature specimens is often strongly 
and abruptly sinuous, or impressed in the middle; cardinal area very 
small but well-defined and a little arched; foramen generally a little 
higher than wide; beak small, arched, and projecting little beyond the 
hinge line, being distinctly less prominent than that of the other valve. 
Dorsal valve gibbous and regularly arched ; beak prominent, strongly 
incurved; cardinal area rather narrow and distinctly arched ; anterior 
margin in large specimens often emarginated for the reception of the 
deflected edge of the other valve. Surface ornamented with fine, regular, 
radiating striae, which bifurcate and increase by intercalation so as to 
preserve a nearly uniform size and arrangement on all parts of the shell, 
those on each side of the beaks curving gracefully outwards to the poste- 
rior lateral margins, while distinct subimbricating marks of growth 
traverse the valves concentrically. 
Breadth (of a large adult specimen), 1.88 inches; length, 1.56 inches; 
convexity, 1.05 inches. 
The adult specimens of the above described shell in the 
collection, are much larger than the typical examples of O. 
iowensis, figured in the Iowa Report, and generally have the 
mesial sinus of the ventral valve so strongly impressed at the 
immediate front as to impart a peculiar sharply emarginate 
outline to the anterior border not seen in any of the Iowa 
examples I have had an opportunity to examine, though 
smaller specimens have the sinus much more shallow and the 
front but faintly sinuous in outline, so as to agree well with 
examples from Iowa. Internal casts of the dorsal valve agree 
more nearly with that of a supposed variety of the Iowa 
species called, in the geological report of that State, O. iow- CHICAGO ACADEMY OF SCIENCES. 
91 
ensis v&r.fumarius than with those of the typical O. iowends. 
It may possibly be distinct specifically from the latter, but I 
am in doubt whether or not in that case it may not have to 
take the name fumarius. 
On comparing this shell with O. McFarland figured on the 
same plate, the species under consideration will be seen to 
differ materially in its broader, more rounded, and more com- 
pressed form, and less straightened posterior lateral margins. 
A comparison of a number of fine specimens shows these 
differences to be constant at all stages of growth. 
Locality and position. Mouth of the Clear Water, on 
Athabasca river. Collected by Maj. K. Kennicott. 
Family PEODUCTIDAE. 
Genus JProdllCtUS Sowerby. 
Productus dissimilis Hall? 
Pl. XIII, fig. 3. 
Produdus dissimilis Hall, Iowa Report, Vol. I (1858), Part 2nd, p. 497, pL iii, fig. 7 
a, b, c, t*, e. 
So far as the rather imperfect specimens of the little shell 
figured under the above name afford means of comparison, 
they agree well with examples of P. disdmilis from Iowa, not 
only in form but in the surface markings of both valves. It 
should be explained, however, that the specimens figured 
have had the extremities of the cardinal margin broken 
away, so as to give an unnatural roundness to the general 
outline. The little spine bases on figure 3 a, are also repre- 
sented proportionally too large, and too erect. 
Length and breadth each about 0.57 inch; convexity, 0.23 
inch. 
Locality and position. ClearWater river; Devonian, (Ham- 
ilton group.) 
JProductus ? 
PI. XIII, fig. 4. 
This shell is evidently related to the last, and yet seems to 
present specific differences. In the first place, it generally 92 
TKANSACTIONS OF THE 
has its hinge proportionally more extended, and more angular 
at the lateral extremities; while the striae on its ventral 
valve are finer, more crowded, and more waved. It also 
differs in showing scarcely more than minute traces of spine 
bases over the disc of the ventral valve. Like the P. dis- 
similis, its dorsal valve is marked by distinct concentric 
wrinkles not seen on the other valve, but these are more 
imbricating, and show traces of radiating striae not seen on 
that valve of P. dissimilis. These radiating striae, however, 
are represented too distinct and too continuous on fig. 4 c, d, 
while the concentric markings are made to curve too much 
outwards as they approach the cardinal margin. The speci- 
mens are too imperfect to admit of a very satisfactory com- 
parison with foreign species. 
Length, 0.61 inch; breadth, 0.65 inch; convexity, 0.24 
inch. 
Locality and position. In dark bituminous limestone, on 
the south side of Great Slave lake, near Fort Resolution. 
Devonian. 
Productus ? 
PI. XIII, fig. 5. 
Having but an imperfect cast of a ventral valve of this 
shell, it is not possible for me to characterize it, or to deter- 
mine whether or not it is new; especially since several 
apparently similar forms have been named and imperfectly 
characterized from equally unsatisfactory material from the 
Hamilton and Chemung groups of New York. It has been 
thought desirable, however, to figure it, in order to give as 
full a representation as possible of the fauna of the Hamilton 
group beds at these distant northern localities. The reader 
should understand that the costae are represented too coarse 
and too continuous on fig. 5 a. They are more properly 
elongated, more or less confluent nodes, as on fig. 5 b, rather 
than continuous costae, and probably supported spines. 
Locality and position. Lockhart river, lat. 67 deg. 15 rain. 
N. Devonian; (Hamilton group.) 93 
CHICAGO ACADEMY OF SCIENCES. 
Genus Chonetes Fischek. 
Chonetes pusilla Hall? 
PL XIII, fig. 2. 
It is with considerable doubt that this little shell is here 
referred to C. pusilla, not only in consequence of the fact that 
only very imperfect specimens were obtained, all imbedded 
in the matrix, but because it seems to be rather more coarsely 
striated, while its striae bifurcate farther from the beak, and 
are apparently marked by stronger concentric striae. As I 
only have a description without figures of O. pusilla for com- 
parison, I am not fully satisfied that our shell is distinct, 
though it probably is. 
Chonetes pusilla Hall, Tenth Report Regents Univ. New York-(1851), p. 109. 
In the same matrix fragments of another species, with 
much finer radiating and concentric striae, are seen. 
Length, 0.23 inch; breadth, 0.26 inch; convexity, about 
0.08 inch. 
Locality and position. Dark bituminous limestone, near 
Fort Resolution, on the south shore of Great Slave lake. 
Family RIIYNCHONELLIDAE. 
Genus Hhynchonella Fischer, 1809. 
Hliynchonellci ccistanea Meek. 
Pl. XIII, fig. 9. 
Shell longitudinally suboval, or a little longer than wide, moderately 
ventricose in mature examples ; lateral margins subparallel, but broadly 
convex in outline; front prominent. Ventral valve convex in the 
umbonal region, and depressed into a broad, flat, rather shallow mesial 
sinus in the front, where it is produced into a more or less prominent, 
rounded projection filling a corresponding sinus in the margin of the 
other valve; beak small and closely incurved over that of the opposite 
valve; anterior lateral margins on each side of the mesial sinus promi- 
nent and sharp. Dorsal valve one-third to one-half more convex than 
the other, curving strongly down on each side and at the beak, though 
but slightly in front, where it is a little elevated, so as to form a low, 
undefined, flattened mesial fold, scarcely traceable to the middle of the 
valve, and usually marked by a very faint impression along the middle; 
beak nearly as prominent as that of the other valve, and strongly in- 94 
TRANSACTIONS OF THE 
curved beneath it. Surface apparently nearly smooth, but at the front 
provided with a few very obscure, rounded plications, from two to four 
or five of which occupy the mesial fold and sinus, and some two or three 
the antero-lateral margins on each side. Under a good magnifier there 
are also to be seen traces of very obscure, fine, radiating and concentric 
striae. 
Length of a medium-sized specimen, 0.96 inch; breadth, 0.79 inch; 
convexity 0.60 inch. 
This shell is not very closely allied to any form with which 
I am acquainted. The fully developed, more gibbous ex- 
amples bear some resemblance to JR. subcuboides, of the N. Y. 
Tulley limestone; but still they differ so clearly as to render 
a comparison scarcely necessary. In the first place, this 
differs in being less ventricose, and never transverse, the 
length always exceeding the breadth, while its plications 
are less numerous, and much more obscure. Indeed on most 
examples they are but feebly defined at the immediate front, 
while in young specimens they are almost, or entirely wanting. 
Another marked feature in this species is, that the deflected 
portion of the anterior margin of the ventral valve, occupying 
the sinuosity in the front margin of the dorsal, is never so 
strongly curved as to meet the latter at right angles, but at a 
more or less acute angle. So that the front of the shell, in 
looking directly down upon either valve, instead of being 
sinuous in the middle, is prominent and abruptly rounded, or 
even subangular in outline. In mature specimens, the margins 
of the valves in front, on each side of the sinus, are deflected 
upwards (or more properly downwards, when the shell is 
placed with the ventral valve down), and meet at an acute angle, 
so as to form a sharp carina around each antero-lateral margin. 
The middle plication is usually larger and more distinct in 
the sinus at the front of the ventral valve than any of the 
others, and corresponds to an obscure depression along the 
middle of the mesial fold of the dorsal valve. 
There is, in the collection from the same locality, a single 
specimen of a more gibbous form, with more numerous and 
more distinct plications, which also has the lateral margins 
more flattened (laterally) near the beaks, giving the shell 
a somewhat cuneate outline, as seen in looking directly upon CHICAGO ACADEMY OF SCIENCES. 
95 
either valve, (see pi. xiii, fig. 10 a, and 10 hi) If this speci- 
men has not suffered some accidental distortion by lateral 
pressure, it must belong to a distinct species. 
Locality. Lockhart river, lat. 67 deg. 15 min. 1ST., Iona1. 
126 deg. W. 
JRhyncJionella ? 
PI. XV, fig. 4. 
As I only know this species from the internal cast of a 
dorsal valve figured on plate xv, and another fragment of the 
same valve of a smaller individual, I have been unable to 
identify it with any known species; nor am I willing to de- 
scribe it as new, without better specimens for study and com- 
parison. 
Locality. Mackenzie river, forty miles below Fort Good 
Hope. 
Genus JPentamerus Sowekby, 1812. 
JPentamerus borealis Meek. 
PI. XIII, fig. 11. 
Shell subglobose, about as wide as long. Dorsal valve moderately 
convex, being most prominent in the central and umbonal regions ; beak 
incurved, and not projecting much beyond the cardinal margin, which is 
rather straight; front depressed so as to form a shallow, flattened mesial 
sinus, extending but a short distance back from the margin. Ventral 
valve more gibbous than the other, particularly in the umbonal region, 
forming a nearly regular descending arch from the beak to the front, 
where there is a slight, flattened mesial prominence, causing a mode- 
rately distinct sinuosity in the margin, occupied by a corresponding pro- 
jection of the edge of the other valve; beak prominent, rather ventri- 
cose, and closely incurved, so as to bring the point nearly or quite in 
contact with the umbo of the other valve. Surface with rather small, 
irregular, distinct radiating costae, which increase by division, each of 
the principal ones, particularly on the sides of the valves, giving off* one 
or more smaller ribs on the outer side, which never equal the others in 
size. 
Length from the front to the beak of the dorsal valve, 0.97 inch ; do. 
to the most prominent part of the umbo of the ventral valve, 1.13 inches; 
greatest breadth, 1.09 inches; convexity of the two valves, 0.91 inch. 96 
TEANS ACTIONS OF THE 
A rather remarkable peculiarity of this shell is the appear- 
ance of a narrow cardinal area (not a true area), which seems 
to be common to both valves, and extends out to the ex- 
tremities of the hinge. Internal casts, however, show two 
very slightly diverging, or nearly parallel septa, extending 
about one-third of the length of the dorsal valve, forward 
from the beak, and one in the ventral valve, exactly as in 
Pentamerus, with which the form of the shell agrees also. 
In form, and the size of the costae, this shell presents much 
the appearance of the well known Pentamerus Knightii of 
Soweeby, from which, however, it differs in the possession of 
a mesial sinus and fold, as well as in having its dorsal valve 
less ventricose. It also resembles P. aratus of Coxead, but 
differs in having its mesial sinus in the dorsal valve instead of 
the ventral. It also differs in not having a smooth space, 
without costae, on each side of the beaks. From P. galeatus, 
which presents very nearly the same form, and also has its 
mesial sinus in the dorsal valve, it will be readily distinguished 
by its much smaller and more sharply defined costae. 
Locality and position. Anderson river. Devonian, (Ham- 
ilton group.) 
Genus Atvypa Dalman, 1827 
Atrypa aspera Schlotheim, (sp.) 
PI. XIII, fig. 12. 
Terebratula aspera Schlot., Petref. (1820), p. 263, t. xviii, fig. 3. 
Although none of the specimens of this species in the collec- 
tion show the interior, I have scarcely a doubt in regard to 
their identity with the well known A. aspera, since they agree 
exactly in all their external characters, with the Hamilton 
group specimens from New York, and from various other 
localities, now before me, as well as with the figures and 
descriptions of European specimens. It seems to be quite 
common and well preserved at numerous localities in this dis- 
tant northern country. 
Atrypa aspera Kalman, Vet. Akad. Handl. (1827), t. iv, fig. 3, etc. 
The specimen figured is from Lockhart river, lat. 67 deg. 15 
min. N. Other specimens are from the “ Ramparts,” and Fort CHICAGO ACADEMY OF SCIENCES. 
97 
Good Hope, on Mackenzie river, while a few examples of the 
same shell were found by the Rev. Mr. Kirby, on Porcupine 
river, Russian America. Mr. McFarlane also found it on 
Anderson river, lat. 67 deg. N., long. 126 deg. W. 
Atrypa reticularis Linn., (sp.) 
PL XIII, fig. 13. 
Anomia reticularis Linn., Syst. Nat., 12th Ed., I (1167), p. 1152. 
Terebratulitespriscus Schlot., Petref. I (1820), p. 262; II, p. 68, 69, t. xvii, f. 2; t. 
xx, f. 4. 
Anomites reticularis Wahlenb., Act. Soc. Upsalensis, VIII (1821), p. 65. 
Terebratula affinis Sowerby, Min. Conch. IV (1823), p. 24, pi. cecxxix, fig. 2. 
Atrypa reticularis Dalman, Vet. Acad. Handl. (182*1), p. 121, pi. iv, fig. 2, etc. 
Of tills widely distributed and well known type (including, 
as there is reason to think, several closely allied species), there 
are, in the collections under consideration, a number of well 
preserved specimens from distantly separated localities. Those 
figured on plate xiii, were collected by Mr. Kennicott, on 
Clear Water river,near its connection with Athabasca river, lat. 
56 deg. 25 min. N., long. 111° W. Most of the specimens from 
this locality are large, and belong to the dilated variety (or 
species) so common in the Hamilton group of New York. 
Some of them are much larger, and even more extended later- 
ally than that represented by figure 13 <2, of ph xiii, while 
others present the form represented by figure 13 b. Others 
of the same types were also found by Mr. McFarlane on 
Anderson river, lat. 67 deg. N., long. 125 deg. W. It is also 
common on Mackenzie river, at the “Ramparts,” and near 
Fort Good Hope. Smaller specimens were likewise found 
by Mr. Kennicott, near Fort Resolution, on Great Slave lake. 
Family SPIRIFERIDAE. 
Genus Cyvtina Davidson, 1858. 
Cyrtina JBillingsi Meek. 
PI. XIV, fig. 6. 
Shell of medium size; hinge line less than the greatest breath, and 
obtusely angular, or somewhat rounded at the extremities. Ventral 98 
TRANSACTIONS OF THE 
valve prominent at the umbo, from which it slopes abruptly, with a 
moderately convex outline, to the anterior and lateral margins; provided 
with a broad, very shallow, undefined mesial sinus in front; beak ob- 
tusely angular, and a little curved backwards; area triangular, some- 
what longer on the hinge line than on either of angular lateral margins, 
slightly arched and inclined backwards over the hinge, and showing 
more or less distinct transverse marks of growth; foramen very narrow, 
or less than half as wide as high, closed below the middle by a mode- 
rately convex deltidium, which (in the specimen examined), is deeply 
emarginated above by a large oval aperture with beveled margins. 
Dorsal valve wider than long, truncato-subelliptical, much compressed 
or nearly flat, most convex between the middle and the umbo, which 
is compressed and scarcely distinct from the hinge margin; lateral 
margins flat, or a little concave; front very slightly raised by the shal- 
low sinus of the opposite valve. Surface ornamented by about forty 
rounded and faintly defined radiating costae on each valve, ten or eleven 
of which occupy the very shallow mesial sinus of the dorsal valve, and 
about the same number the corresponding slight prominence of the 
ventral valve. These costae sometimes bifurcate, or increase by the 
intercalation of others, which die out before reaching the beaks, par- 
ticularly on the middle portions of the valves. Faint traces of very 
fine crowded concentric striae, and a few stronger lines of growth mark 
the valves in the opposite direction; while, with a good magnifier, 
minute granules may be seen on all parts of the surface. Exfoliated 
surfaces also show, under a magnifier, the minutely punctate structure 
characteristic of the genus. 
Length from the front to the hinge, 0.40 inch; do. from front to point 
of beak of ventral valve, 0.60 inch ; breadth, 0.60 inch. Length of 
hinge, 0.50 inch; convexity of the two valves, 0.33 inch, about four- 
fifths of which is occupied by the ventral valve alone. 
I have not seen the interior of this species, but as it has 
the form and general aspect of a Cyrtia, or Cyrtina, and 
shows a punctate structure it doubtless belongs to the latter 
group. As near as can be determined, from a description 
alone, it would seem to present much the general appearance 
of Cyrtina occidentalis {Cyrtia occidentalis of Swallow, Trans. 
St. Louis Acad. Sci., Vol. I, p. 648), from the Hamilton 
group of Callaway county, Missouri, from which it differs in 
having plications on the mesial prominence. From Cyrtina 
MUsowaends {Cyrtia Missoui'iensis Swallow), which has 
plications on the mesial elevation, it differs in being much 
less angular at the extremities of the hinge, and in having 
much more numerous and smaller plications on each side of CHICAGO ACADEMY OF SCIENCES. 
99 
the mesial elevation, which is less prominent and less defined. 
It will be at once distinguished from Cyrtina hamiUonensis, 
and all the nearly allied species by its much smaller and more 
numerous costae, and less prominent and plicated mesial 
region. 
Named in honor of Mr. E. Billings, the able palaeontolo- 
gist of the Canadian Geological Survey. 
Locality and position. Clear Water river, a tributary of 
Athabasca river. Devonian of the age of the Hamilton group. 
Cyrtina hamiUonensis Hall. 
PL XIV, fig. 10 ; also, figs. 5 and 7 ? 
Cyrtia hamiUonensis Hall, Tenth Report Regents University, New York (1857), p. 
126; Billings, Devonian Fossils, Canada West (1861), p. 53, figures 80-82. 
Compare Cyrtina heteroclita—Cyrtia heteroclita of authors. 
The form here referred to the above-named Hamilton 
group species agrees so very closely in all its known charac- 
ters with New York examples of that shell, that I can see no 
sufficient reason for regarding it as a distinct species. I know 
nothing of its internal either from the Arctic 
specimens under investigation, or from New York examples, 
but from the general form of these shells, taken in connection 
with their distinctly punctate shell structure, there is little 
room for doubting the propriety of referring them to the 
genus Cyrtina.5 
The specimen represented by figures 5 a, b, and 7 a, b, of 
the same plate, differs from that from which figure 10 was 
drawn, in having the mesial sinus and fold more angular in 
the middle, and the foramen unclosed by deltidium, and 
hence may possibly be a distinct species. As the deltidium, 
however, may have been broken out in detaching the speci- 
men from the matrix, or otherwise removed, and New York 
5 Cyrtia umbonccta Hall, Iowa Report, pi. v, fig. 2 a, 6, c, has a punctate structure, and 
as may be seen by the figure of the interior, is a true Cyrtina. I have also ascertained 
that Cyrtia acutirostris Shumard, Mo. Report, Part 2nd, p. 204, pi. c, fig. 3 a, 6, c, has 
the internal characters of Cyrtina. As Cyrtia triquetra Hall, Iowa Report, p. 513, 
also shows, under a magnifier, a distinctly punctate structure, it must likewise fall into 
the genus Cyrtina. Hence the names of these shells will have to be written Cyrtina 
umbonata, Cyrtina acutirostris and Cyrtina triquetra. 100 
TRANSACTIONS OF TIRE 
specimens of Q. Jiamiltonensis vary in the roundness or angu- 
larity of the sinus and fold, I can with the material at hand 
for comparison, but regard this as a variety of the same 
species. 
Locality and portion. The form represented by figure 10 
was collected by the Rev. W. W. Kiiiby, on Porcupine river, 
Russian America, long. 140 deg. W., lat. 67 deg. N. The 
other example, from which figures 5 a, b, and 7 a, b, were 
drawn, was collected by Major Kennicott, at the “Ramparts,” 
on Mackenzie river. 
Cyrtina panda Meek. 
PL XIV, fig. 8. 
Shell pyramidal, wider than long; hinge line less than the greatest 
breadth of the valves in adult examples ; lateral extremities obtusely 
angular or somewhat rounded. Dorsal valve truncato-subelliptic, nearly 
flat, or but little convex; beak not prominent; mesial fold rounded, 
nearly flat, excepting at the front, where it is a little raised, occupying 
distinctly more than one-third the entire breadth of the valve at the 
anterior margin, but narrowing very abruptly to the beak. Ventral 
valve very convex; sides sloping abruptly from the beak to the front 
and lateral margin; beak high, not indfPrved, but sometimes twisted to one 
side; area large, well-defined, triangular, nearly flat, or slightly arched, 
and finely and regularly striated both ways; deltidium narrow, a little 
convex, and at the upper extremity perforated; mesial sinus very shallow 
and rounded, causing a slight projection into a corresponding recess in 
the margin of the other valve in front. Surface ornamented by 10 to 12 
small, regular, simple radiating cost* on each side of the mesial sinus 
and fold, which latter are with’out costse, but marked with very fine, 
obscure radiating striae. Fine, obscure lines of growth also mark the 
entire surface concentrically, in well preserved specimens. 
Length, 0.45 inch; breadth, 0.66 inch; convexity, 0.51 inch. 
I was at first inclined to regard this as a mere variety of 
the C. hamiitonen&is, supposing its smaller and more numerous 
costae a difference of scarcely specific importance. On closer 
examination, however, by the aid of a magnifier, fine, regular 
radiating striae (not represented in the figures), were observed 
on its mesial fold and sinus, a character I believe entirely 
unknown in that shell. It is possible that both this and the 
C. hamiltonensis may be identical with European forms some- 
times referred to C. heteroclita, as it is manifest several species CHICAGO ACADEMY OF SCIENCES. 
101 
liave often been included under that name. As they seem to 
me, however, to differ specifically from the forms referred by 
Mr. Davidson to C. heteroclita, we do not feel warranted in 
referring either of these forms to that species. 
Locality and position. Onion river, long. 125 deg. W., lat. 
67 deg. H. 
Genus Spirifer Soweeby, 1815. 
Spirifer Kennicotti Meek. 
PL XIY, fig. 9. 
Shell subsemicircular, rather compressed; valves nearly equally con- 
vex ; length less than half the breadth; greatest breadth on the hinge 
line, which is extended apparently into a point at each extremity. 
Dorsal valve most convex near the middle, thence curving more rapidly 
to the beak than to the front; sides sloping very gradually and becom- 
ing rather flattened near the extremities ; beak somewhat compressed, 
scarcely projecting beyond the hinge line, and with the linear area a 
little incurved; mesial fold narrow and scarcely distinct from the general 
convexity of the central region, excepting near the front. Ventral valve 
very slightly less convex than the other, most prominent between the 
middle and the beak; lateral slopes a little less flattened than in the 
dorsal valve; mesial sinus narrow, rather shallow, with rounded margins, 
continued nearly to the beak, from which it widens and deepens very 
gradually to the anterior margin, where it produces a moderately dis- 
tinct, narrow emargination; beak a little incurved and more prominent 
than that of the other va-lve, but not produced much beyond the margin 
of its own area, which is narrow, with nearly parallel margins, and 
inclined, with a slight curve, back over the hinge ; foramen j)resenting 
nearly the form of an equilateral triangle. Surface with about twenty-six 
to thirty simple, regular, well-defined, radiating costae, on each side of 
the mesial fold and sinus, separated by depressions of their own breadth. 
The mesial sinus and depression are also each occupied by six or seven 
more or less bifurcating costae. By the aid of a good magnifier, faint 
traces of numerous minute, closely arranged concentric striae and 
granules are also seen on all parts of the surface. 
Length, 0.64 inch; breadth, 1.45 inches; convexity, 0.38 inch; height 
of area in ventral valve, 0.10 inch. 
This shell is rather closely allied to S. acanthotus Hall 
from the Hew York Chemung group. On comparison with 
good specimens of that species from Hew York, however, I 
find it presents the following well-marked differences. In 
the first place, its mesial fold and sinus are much narrower in 102 
TRANSACTION'S OF THE 
front, while the former is more prominent, less flattened, and 
not so well defined by the greater depth of the marginal furrow 
on each side, and the latter has rounded, instead of angular 
margins. Again, our shell shows only six or seven of the 
small costae occupying the mesial fold and sinus at the front, 
while double that number may be counted upon the fold, 
or in the sinus of S. acanthotus. In addition to these differ- 
ences, the species under consideration is longer in proportion 
to its transverse diameter, and has the costae near each lateral 
extremity directed much less obliquely outwards, and the 
pointed extremities less compressed, and more abruptly sepa- 
rated from the outline of the lateral margins than in S. 
acanthotus. 
Named in honor of Maj. Robert Ketoticott, its discoverer. 
Locality. Liard’s river, lat. 60 deg. 15 min. N., long. 123 
deg. W. It was found loose, but most probably belongs to 
rocks of about the age of the Hamilton group in the immedi- 
ate neighborhood. 
Spirifer compactus Meek. 
Pl. XIY, fig. 11. 
Shell subglobose, a little wider than long; greatest transverse diameter 
usually at some point between the middle and the cardinal margin; hinge 
line equaling about two-thirds the greatest breadth of the valves; 
lateral margins scarcely ever even obtusely angular at their connections 
with the hinge, but rounding regularly into the front, which is sometimes 
very faintly sinuous at the termination of the mesial fold. Dorsal valve 
rather gibbous, but a little less so than the ventral; mesial fold rounded, 
depressed or moderately prominent, and without costae; beak projecting 
a little beyond the hinge line, and rather distinctly incurved over its 
narrow cardinal area. Ventral valve most gibbous in the umbonal 
region; beak prominent and distinctly incurved ; mesial sinus moderate, 
extending to the beak, rounded or very faintly subangular, widening 
gradually forward without very distinctly defined margins to the front, 
where it terminates in a semicircular projection, filling a corresponding 
recess in the margin of the other valve ; area moderately high and arch- 
ing with the beak, rather well defined, but without angular margins, and 
marked by distinct transverse striae, crossed by very minute vertical 
lines; foramen presenting nearly the form of an equilateral triangle, 
or rather higher than wide. Surface with about nine to ten simple, 
rounded, rather depressed costae on each side of the mesial fold and 
sinus, and numerous fine, very regularly arranged, equal, crowded CHICAGO ACADEMY OE SCIENCES. 
103 
concentric striae, which are regularly arched in crossing the ribs. Under 
a good magnifier, on protected portions of well preserved specimens, 
traces of extremely small radiating striae, apparently produced by regu- 
larly disposed granules, may also be seen. 
Length of a medium sized specimen, 0.90 inch; breadth, 0.96 inch; 
convexity, 0.70 inch; breadth of mesial fold and sinus of the front, 0.35 
inch. Some specimens are proportionally more gibbous. 
This is a neat, rather robust shell, and may be regarded as 
a representative of 8. Jimbriatus Conrad, (sp.) Its much more 
gibbous form, shorter hinge, and smaller, as well as more 
numerous and more distinctly defined costae, however, will 
readily distinguish it from that species. Its concentric mark- 
ings also differ in being all uniform, closely arranged striae, 
without imbricating lamellae. 8. corticosus Hall (judging 
from a description only), seems to be a somewhat analogous 
shell, but differs in having a longer hinge line and a narrow 
cardinal area. Our shell, however, is evidently more nearly 
allied to S. undiferus Koemer, than to any of the American 
forms mentioned above. Indeed, after comparison with Mr. 
Davidson’s excellent figures of that variable species, it is 
with some hesitation that I have concluded to regard the Arctic 
form as a new species. I am led to do so, however, from the 
following differences. In the first place, our shell never has 
the mesial fold flattened along the middle as we most gener- 
ally see in 8. undiferus, while it shows no traces of obscure 
costae on the sides of the mesial sinus. Again, its concentric 
striae are much finer and more crowded than those of 8. undi- 
ferus, and differ in showing, under a magnifier, microscopic 
crenulations apparently produced by very minute radiating 
markings. 
Locality. Lockhart river, lat. 67 deg. 65 min. N., long. 
126 deg. W. Collected by E. W. McFarlane. 
Subgenus JKartinia McCoy, 1844. 
Spirifer {Martinia) sublineatus Meek. 
PL XIV, fig. l. 
Shell small, subcircular, or truncato-orbicular, moderately convex in 
adult specimens; lateral margins rounding gradually into the more or less 
regularly rounded front, and more abruptly into the short hinge; cardinal 104 
TRANSACTIONS OF THE 
margin considerably shorter than the greatest breadth of the valves. 
Dorsal valve subsemicircular, rather compressed and without any traces of 
a mesial fold ; beak small, projecting little beyond the cardinal margin ; 
area small. Ventral valve twice or three times as convex as the other, 
and without a mesial sinus ; area triangular, moderately high, not very 
sharply defined; foramen triangular, higher than wide, unclosed in all 
the specimens examined. Surface very nearly smooth, but showing, 
under a magnifier, faint traces of very fine concentric striae, and obscure 
indications of radiating lines. Internal casts of the ventral valve with a 
faint furrow extending along the middle, on each side of which there is a 
shallow, flat impression, extending from the umbonal region to each 
antero-lateral margin. 
Breadth of a large individual, 0.62 inch; length, 0.60 inch; convexity, 
0.34 inch. 
This little shell has the general aspect of young or 
dwarfed examples of S. lineatus Martin (sp.), from which it 
differs in always being without the regular imbricating con- 
centric markings of that species; while it is in all cases 
without any traces of a mesial fold or sinus. It is also less 
convex and more inequivalve than S. lineatus, and the flat- 
tened furrows on internal casts left by corresponding ridges 
on the interior of the ventral valve, is a feature not men- 
tioned in descriptions or represented by figures, of that 
species. 
It is probably more closely allied to S. glans-cerams, of 
White, described from rocks of the age of the Hamilton 
group at Iowa City, Iowa. From the fact, however, that Dr. 
White’s species is described as being very small and globose, 
even more globose than the common coal measure form of the 
west usually referred to S. lineatus, I infer that our shell is 
larger and much less convex; it also always wants the faint 
mesial sinus, and consequent slight emargination of the front, 
mentioned in the description of S. glans-cerams. 
Locality. Common in the dark bituminous limestone, near 
Fort Resolution, on the south side of Great Slave lake. 
Spirifer (Martinia) Hichardsoni Meek. 
PI. XIV, fig. 2. 
Shell small, wider than long, rather gibbons ; hinge line about as long 
as half the transverse diameter of the valves; lateral margins rounding CHICAGO ACADEMY OF SCIENCES. 
105 
somewhat abruptly into the hinge margin, and converging Avith a slightly 
convex outline to the front, which is a little truncated, or very faintly 
sinuous in the middle. Ventral valve about one-third more convex than 
the other, provided in front with a shallow, subangular, undefined mesial 
sinus, which dies out before reaching the middle of the valve; beak 
rather pointed, moderately prominent, and incurved but not projecting 
more than one-eighth the entire length of the shell beyond that of the 
other valve, from which it stands a little remote; area broadly triangular, 
not distinctly defined, arcuate ; foramen triangular, unclosed, higher than 
wide. Dorsal valve moderately convex, and without a mesial fold 
even at the immediate front; beak small, projecting little beyond the 
hinge, and not distinctly incurved, provided with a narrow area. Surface 
(of internal cast) showing faint indications of eighteen to twenty remote 
linear, radiating ridges on each valve, so indistinct as to leave doubts 
whether or not they were connected with external costae. 
Length, 0.55 inch; breadth, 0.65 inch; convexity, 0.44 inch. 
This species is allied to the last, but differs in being propor- 
tionally wider, and although the umbo of its ventral valve is 
more gibbous, it projects porportionally less beyond that of 
the opposite valve, from which it is more distant. It also 
differs in having the anterior margin of the ventral valve 
provided with a shallow sinus, which imparts a faintly sinuous 
outline to the front. A more important difference, however, 
is the indication on the internal cast, of obscure costse; while 
the cast of the cavity of the beak of the ventral valve in $. 
sublineatus and its other internal markings, are entirely 
different. 
As near as can he determined from a description alone, 
without a figure, measurements, or other means of knowing 
whether that is a very small, or a very large shell, this species 
would seem to he related to S. dubius of Hall. It differs 
however, from the proportions of that species in being wider 
than long, instead of longer than wide, or with length and 
breadth equal, while the beak of its ventral valve projects 
much less beyond that of the opposite valve, and its dorsal 
valve is without a mesial fold. 
Named in honor of the distinguished Arctic explorer and 
naturalist, Sir John Richardson. 
Locality. Fort Good Hope, on Mackenzie river, lat. 66 deg, 
1ST., long. 128 deg. W. 106 
TRANSACTIONS OF TIIE 
Spirifer (Martinia) 'meristoides Meek. 
PI. XIV, fig. 3. 
Shell varying from longitudinally suboval to suborbicular, being some- 
times longer than wide, and in other examples slightly wider than long, 
generally rather ventricose in adult specimens; hinge line very short 
and passing so gradually into the regularly rounded lateral margins as 
scarcely to appear straight at all; front narrowly, or more or less regu- 
larly rounded. Dorsal valve convex, but less so than the other, without 
a trace of a mesial fold, though the immediate margin at the middle of 
the front is very slightly raised to give room for an obscure projection of 
that of the other valve; beak small, but slightly prominent and incurved; 
area very narrow and curved. Ventral valve gibbous, sometimes rather 
strongly so, without a mesial sinus; beak prominent, incurved, in ventri- 
cose specimens sometimes almost folded down upon the other so as to 
close and hide the foramen; area very small and obscure, often neai’ly 
obsolete; foramen triangular, rather higher than wide, and not closed by 
a pseudo-deltidium. Surface marked by fine, rather obscure concentric 
strife, with a few rather strong concentric ridges of growth, usually 
passing over the middle of the ventral valve, and between that and the 
front. Internal cast showing distinct radiating markings. Internal 
spires rather large, and consisting (in a small specimen) of about six 
turns. Socket plates of dorsal valve thin, prominent, approximate, and 
but slightly diverging forward. 
Length of a mature specimen, 0.73 inch; breadth of do., 0.65 inch; 
convexity, 0.47 inch. 
This is so remarkable a form, that it was some time before 
I could come to any conclusion respecting its generic relations. 
Its longitudinally oval form, extremely short hinge line, pass- 
ing gradually into the rounded lateral margins, together with 
the rudimentary condition of its area, gives it much the 
appearance of a Merista. This deceptive appearance is also 
increased by the beak of the ventral valve being sometimes 
so closely curved down upon that of the other valve as to 
completely hide the triangular foramen and obscure area. 
This latter character, however, it is easy to see, is due to the 
shell taking, as it were, a second growth after it had attained 
about half its usual size. In most of the specimens, the 
growth seems to have been very gradual and regular until 
they attained a diameter of about 0.50 inch, at which time 
there seems to have been a period of rest, and the shell was 
then wider than long, having much the aspect of a form in CHICAGO ACADEMY OF SCIENCES. 
107 
our western coal measures, described by Dr. Shttmaed, under 
the name of Spirifer plano-convexus. After this there was a 
period of rapid, more irregular growth, mainly of the anterior 
and antero-lateral margins, more particularly of the ventral 
valve, which changes the form of the whole shell to a longi- 
tudinally oval outline, and as it were, spreads open the valves, 
so as to bring the beak of the ventral valve down upon that 
of the other. 
If the name Ambocoelia should be retained, the name of this 
species would become Spirifer {Ambocoelia) meristoides, since, 
notwithstanding its extremely short hinge, and obscure cardi- 
nal area, it has the peculiar socket plates, and muscular scars 
of the type of that proposed group. It is very doubtful, 
however, whether any well defined line of demarkation can 
be drawn between that type and the group of smooth Spiri- 
fers for which McCoy proposed the name Martinia. 
Locality. Anderson and Lockliart rivers, lat. 67 deg. 15 
min. N., long. 126 deg. W. 
Spirifer (Martinia) Frariklinii Meek. 
Pl. XIV, fig. 12. 
Shell rather large, orbicular, subquadrate in outline, moderately gib- 
bous ; hinge equaling about three-fourths the greatest breadth, and 
rounded at the extremities. Dorsal valve moderately convex, (the most 
prominent part being in the central and umbonal regions), provided near 
the front with a low, undefined mesial prominence which scarcely reaches 
the middle, and is marked by a shallow longitudinal depression; beak 
extending little beyond the hinge and rather distinctly incurved ; area 
narrow and not extended to the extremities of the hinge, and distinctly 
arched. Ventral valve more gibbous than the other, its most prominent 
part being between the middle and the beak, which is produced beyond 
that of the other valve, and distinctly incurved; mesial sinus very nar- 
row, shallow, and extended nearly to the beak, forming a short semi- 
circular projection in front, fitting into a corresponding sinuosity in the 
front of the opposite valve ; area moderate, continued to the extremities 
of the hinge; finely striated both ways, and distinctly arched and 
inclined back over the cardinal line—its lateral margins at first sloping 
from the beak, then extending out parallel to the hinge margin for a 
short distance, after which they again slope to the extremities of the 
hinge; foramen broad at the base and narrowing rapidly to the beak, 
closed for half the distance down by a rather convex pseudo-deltidium, 108 
TKANSACTIONS OF THE 
which is arched on the lower margin. Surface apparently nearly 
smooth, excepting a few small marks of growth, but showing, under a 
magnifier, very fine, obscure, closely arranged concentric stria3, with 
some appearance of minute radiating strije. 
Length from front to beak of dorsal valve, 1.47 inches; do. to beak of 
ventral valve, 1.80 inches; greatest breadth, 1.94 inches; convexity of 
the two valves, 1.24 inches; length of hinge, 1.54 inches. 
This species closely resembles some varieties of the well 
known Spirifer glaber, which is said to occur both in the 
Devonian and Carboniferous rocks. It differs, however, from 
all Mr. Davidson’s beautiful figures of the various forms 
assumed by that species in having the lateral margins of the 
area of the ventral valve extended part of the way out parallel 
to the hinge margins, instead of sloping regularly from the 
beak to the extremities of the hinge. This character, how- 
ever, is not very well represented in our engraving. 
It seems also to be related to 8. laevis Hall, from the 
Portage group of New York (Greol. 4th Dist. N. Y., p. 245, 
tig. 1); but differs in the peculiarity of the area already 
pointed out, as well as in having a much broader foramen, and 
a much less deeply impressed mesial sinus, particularly at the 
front margin, while it shows no traces of the few strong folds 
said sometimes to mark the margin of that shell. 
Locality. Mackenzie river, forty miles below the “Ham- 
parts.” 
Genus Itensselaeria Hall, 1859. 
Itensselaeria laevis Meek. 
PI. XIII, fig. 8, and pi. XIV, fig. 4. 
Shell rather above medium size, longitudinally ovate or subelliptic in 
outline, moderately convex in young examples, and very gibbous in 
adult specimens; front generally rather narrowly rounded; lateral margins 
forming broad semiovate or semielliptical curves, not inflected. Dorsal 
valve a little less convex than the other: beak incurved. Ventral valve 
most convex somewhat behind the middle; beak small, moderately 
prominent, and closely curved over that of the opposite valve; foramen 
small. Surface smooth, with a few very obscure traces of ridges of 
growth. Some of the specimens also show, under a magnifier, very faint 
indications of radiating striae, but it is not clear that they are surface 
markings. CHICAGO ACADEMY OF SCIENCES. 
109 
Length of a medium sized adult specimen, 1.77 inches; breadth, 1.13 
inches; convexity about 1.10 inches. Smaller specimens proportionally 
less convex. 
This shell is so similar in its external characters to Penta. 
merits elongatus of Vanuxem (Stricklandinia elongata Bil- 
lings, Pensselaeria elongata Hall), that I should have been 
left in some doubt in regard to the propriety of considering it 
distinct, were it not for the fact that Mr. Billings has shown 
Vanuxem’s species to possess the internal characters of his 
genus StricJdandinia, while casts of the interior of the shell 
under consideration show no traces of the triangular chamber 
within the beak of the ventral valve as observed in that 
genus. On the contrary, so far as can be determined from 
these casts, this arctic species seems to agree with the genus 
Pensselaeria. It differs from the known species of Pensselaeria, 
nearly resembling it in form, such as P. oroides, P. mary- 
landica, etc., in its smoother surface, and in never having the 
lateral margins inflected. 
The sections examined by transmitted light, under a high 
magnifying power, show the shell structure in our species to 
be finely punctate, the punctures being small and scattering, 
but regularly disposed. 
Locality and position. Onion river, lat. 67 deg. N., long. 
124 deg. W., and forty miles below Good Hope, Mackenzie 
river, lat. 65 deg. 50 min. N., long. 130 W.; also Lockhart 
river, lat. 67 deg. 15 min. N., long. 126 deg. W. The'specimens 
are all casts, in a bard, gray dolomitic rock, breaking witk a 
rough, irregular fracture, and presenting a harsh, granular ap- 
pearance, that might at . a glance, cause it to be mistaken for a 
sandstone, or at any rate for a silicious rock. As this differs 
from the matrix of the other fossils from the same locality, I 
suspect this species to belong to a different rock, possibly 
older than the Hamilton group. It seems to be abundant at 
both localities, and is the only recognizable fossil in the 
masses collected. 110 
TRANSACTIONS OF THE 
GASTEROPODA. 
Family PLEUROTOMARIIDAE. 
Genua Pleurotomaria Defrance, 1826. 
JPleurotomaria ? 
PI. XV, fig. 3. 
The only gasteropod in the collections under investigation, 
is merely an internal cast, with fragments of the shell adhering. 
It is a depressed form, apparently of Pleurotomaria, though I 
have not been able to see well-defined traces of a spiral band 
on the cast, which seems to be round, and without any revolv- 
ing angles or ridges on the periphery or above or below it. 
The umbilicus was moderately large, and a remaining portion 
of the shell shows traces of regular oblique lines of growth 
on the upper side of the body whorl. 
Of course it would be improper to attempt to establish a 
new species upon a single specimen in such a state of preser- 
vation. The figures represent two views, natural size. 
Locality. Clear Water river, near Athabasca river, lat. 56 
deg. 25 min. N., long. Ill deg. W. from Greenwich. 
CEPHALOPODA. 
Family NAUTILIDAE. 
Genus Gyroceras Koninck, 1844. 
Gyroceras Logani Meek. 
Shell curved so as to form apparently one entire volution or more, 
around a free space nearly or quite equaling the dorso-ventral diameter 
at the larger extremity, increasing so as to about double its diameter in 
half a volution. Dorsal and ventral sides6 very broadly rounded, the 
latter being slightly more compressed than the former; lateral margins 
narrowly rounded. Section transversely elliptical, the ventro-dorsal 
diameter being to the transverse as five to seven or eight. Septa deeply 
and regularly concave, separated by spaces on the dorsal side, about 
equal to one-eighth the transverse diameter, and on the ventral by spaces 
equaling only one-eleventh the diameter from the ventral to the dorsal 
6 I use these terms here with relation to the shell only, and not as applied to the 
animal. CHICAGO ACADEMY OF SCIENCES. 
side. Siphon equaling the space separating the septa on the ventral side 
opposite the point of measurement, and located rather less than half its 
own diameter within the dorsal side. 
Surface (of internal cast) ornamented with obtuse undefined ridges, 
which originate on the middle of the narrowly rounded sides and extend 
outwards, but apparently without crossing the dorsum, on each side of 
which they curve more or less backwards. Between each two of these 
ridges, immediately on each side of the middle, a small, somewhat ele- 
vated, subnodose prominence is seen ranging obliquely outwards and 
forward. The principal ridges are arranged at intervals of about one to 
every four or five septa, there being six or seven of them to half of one 
volution. Finer surface markings, if any existed, unknown. 
Greatest diameter of an imperfect specimen measuring seven inches in 
length around the outer side of the curve, and consisting entirely of the 
septate part of the shell, 3.83 inches; diameter of the free space within 
the curve, 1.50 inches. Ventro-dorsal diameter at the larger end, 1.54 
inches ; transverse diameter of same, 2.30 inches; ventro-dorsal diameter 
at the smaller end (which is imperfect), 0.80 inch; transverse diameter 
of do., 1 inch. 
The specific name is given in honor of Sir William Logan, 
the distinguished director of the Canadian Geological Survey. 
Locality. Forty miles below Fort Good Hope, on Mackenzie 
river, lat. 65 deg. 30 min. N., long. 130 deg. W. 
Explanation of the Plates. 
Plate XI. 
Fig. 1. Zaphrentis recta: — side view; a, view of the calice; b, 
longitudinal section to show the internal structure; <?, transverse section. 
Fig. 2. Zaphrentis McFarlanei:—side view, looking obliquely into 
the calice ; a, longitudinal section; b, view of calice. 
Fig. 3. Aulophyllum ? Richardsoni: — side view of a specimen a 
little flattened by pressure, looking obliquely into the calice ; g, longitu- 
dinal section. 
Fig. 4. Combophyllum multiradiatum:—view of upper side, show- 
ing the very shallow calice and septal fossette; a, side view. 
Fig. 5. Palaeocyclus Kirbyi: — view of under side, showing con- 
centrically wrinkled epitheca ; a, side view; 5, view of upper side, show- 
ing the very shallow calice and septa. 112 
TRANSACTIONS OF THE 
Fig. 6. Cysteophyllum americanum var. arcticum:—side view of 
a somewhat worn specimen; a, longitudinal section of same; b, trans- 
verse section of same. 
Fig. 7. Smithia Verrilli: — side view showing the inferior surface 
protected by the wrinkled epitheca, and the summit with its calices; a, 
upper view of same; b, polished transverse section, enlarged about two 
diameters, to show the confluent septal radii and extremely thin dissepi- 
ments. 
Fig. 8. Cyathophyllum arcticum: — view of upper side, showing 
the calices; a, a longitudinal section of one of the corallites enlarged so 
as to show the internal structure, calice, septa, etc.; b, a transverse sec- 
tion of one of the corallites a little enlarged. 
Fig. 9. Alveolites vallorum: — a fragment showing two sides ground 
off, and the upper surface with the calices, natural size: a, calices 
enlarged. 
Fig. 10. Favosites polymorpha: — a fragment of a bifurcating 
branch, showing the calices, rounded from the thickening of the walls 
between; a, a transverse section of one of the branches, natural size, 
showing the more angular character of the cells within. 
Plate XII. 
Fig. 1. Orthis McFarland: — a, cardinal view of a small specimen 
apparently of this species, from Lockhart river; b, enlargement of sur- 
face striae of same; c, front view of a typical specimen, which is mainly 
an internal cast, from Fort Good Hope; d, ventral view of an internal 
cast of a smaller individual; e, ventral view of the typical specimen ; 
f, cardinal view of same; y, dorsal view of same. 
Fig. 2. Orthis iowensis ? — a, dorsal view of an internal cast; b, 
ventral view of an internal cast with some portions of the shell remaining ; 
c, front view of a larger individual; d, side view of same; e, cardinal 
view of a still larger specimen; f, dorsal view of same; <7, ventral view 
of the same; h, front view of a small individual with only a very 
shallow mesial sinus. 
Plate XIII. 
Fig. 1. Lingula minuta: — enlarged’five diameters. 
Fig. 2. Chonetes pusilla?— a, ventral view, natural size; b, section 
through the two valves to show their curve and convexity; c, enlarge- 
ment of surface striae; d, ventral view enlarged. 
Fig. 3. JProductus dissimilis?— a, view of ventral valve ; b, outline 
profile view ; c, view of dorsal valve. CHICAGO ACADEMY OF SCIENCES. 
113 
Fig. 4. Productus, (sp. undt.) — a, ventral valve; 5, outline profile; 
c, surface striae of ventral valve; d, dorsal valve (radiating lines repre- 
sented too distinct). 
Fig. 5. Productus, (sp. undt.) — a, ventral view (costae too coarse 
and continuous); b, side view of same. 
Fig. 6. Strophomena (Strophodonta) demissa: — a, dorsal view, 
showing also the cardinal area; b, outline profile view of same specimen; 
c, ventral view of same. 
Fig. 7. Strophomena (Strophodonta) subdemissa: — a, dorsal view, 
showing also the area; 5, ventral view; <?, outline side view. 
Fig. 8. Bensselaeria laevis: — a, ventral view of a medium sized 
specimen; b, dorsal view of a smaller individual; c, front view of same; 
d, ventral view of same; e, side view of same. 
Fig. 9. JRhynchonella castanea:—a, ventral view; b, front view; 
c, side view. 
Fig. 10. JRhynchonella, (sp. undt.) — a, dorsal view; b, front view. 
Fig. 11. Pentamerus borealis: — a, dorsal view; b} ventral view; 
c, side view. 
Fig. 12. Atrypa aspera: — ventral view. 
Fig. 13. Atrypa reticularis:—a, ventral view of a dilated variety; 
b, ventral view of another specimen with a more rounded cardinal outline. 
Plate XIV. 
Fig. 1. Spirifer (Martinia) sublineatus:—a, profile view of a small 
specimen; 5, dorsal view of same; c, internal cast of a larger individual 
(ventral valve). 
Fig. 2. Spirifer (Martinia) Michardsoni:—a, view of ventral valve 
(mainly an internal cast); b, dorsal view of same; c, cardinal view of 
same. 
Fig. 3. Spirifer {Martinia) meristoides:—a, dorsal view; b, ven- 
tral view; c, side view: d, front view; e, side view of a shorter indi- 
vidual ; f, internal cast, dorsal view; y, internal cast, ventral view; h, 
section of a small specimen, showing internal spires. 
Fig. 4. Bensselaeria laevis:—an internal cast of a ventral valve. 
Figs. 5 and 7. Cyrtina hamiltonensis ?—a, cardinal view; b, side 
view of same. 7—a, view of ventral valve of same; b, dorsal view of 
same. 
Fig. 6. Ctjrtina Billingsi:—a, lateral view; 5, dorsal view; c, car- 
dinal view; d, ventral view. 114 
TRANSACTIONS OF THE 
Fig. 8. Cyrtina panda:—a, dorsal view; b, cardinal view; c, ven- 
tral view; J, lateral view. 
Fig. 9. Spirifer Kennicotti: — a, ventral view; b, dorsal view; c, 
lateral view. 
Fig. 10. Cyrtina hamiltonensis:—a, cardinal view; b, dorsal view. 
Fig. 11. Spirifer compactus:—a, ventral view ; b, lateral view; c, 
front view; d, dorsal view. 
Fig. 12. Spirifer (Martinia) FranJclini: — a, ventral view; b, la- 
teral view; c, front view; d, dorsal view. 
Plate XV. 
Fig. 1. 7 JProetus ? 
Fig. 2. Gyroceras Logani: — a, profile view of an imperfect speci- 
men ; b, view of the concave side of same; c, view of the convex side 
of same. 
Fig. 3. jPleurotomarici) (sp. undt.) — a, profile view; b, view of up- 
per side. 
Fig. 4. Hhynchonella, (sp. undt.) —view of an internal cast of the 
dorsal valve. 
7 The only specimen of this species contained in the collection was lost during the fire 
at the Smithsonian Institution; consequently I have not been able to determine whether 
or not it is identical with any of the known species, and have not attempted to describe it. TRANS. CHICAGO ACADEMY OF SCIENCES 
vot i. PL. XI. 
F.B Meelt, del 
T. Sinclair’s lith., Phila TRANS. CHICAGO A CADE MY OF SCIENCES. 
VOL. I PL.XI1 
‘ I'iul .M. Springer, del. 
T. Sinclair's iilln Phila. TRANS. CHICAGO ACADEMY OF SCIENCES. 
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VOL.I.PL.Xin . 
PM. M. SpiiiLOns , dpi. 
T Sinclair's lith. Phili TUANS MIH’AUO A CADi: MV Ol- SCI KXCKS. 
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