ENGINEER DEPARTMENT, U. S. ARMY. 
GEOGRAPHICAL EXPLORATIONS AND SURVEYS WEST OF THE 
ONE HUNDREDTH MERIDIAN. 
First Lieut. GEO. M. WHEELER, Corps of Engineers, in charge. 
REPORT 
UPON 
VERTEBRATE FOSSILS 
DISCOVERED IN 
NEW MEXICO, 
WITH 
DESCRIPTIONS OF NEW SPECIES. 
Prof. E. D. COPE, 
PALEONTOLOGIST. 
Extract, from appendix ff of the annual report of the 
— CHIEF OF ENGINEERS, 1874. 
' “'WASHINGTON: 
GOVERNMENT PRINTING OFFICE. 
November 28, 1874. c$o-7n^/U'm,e,7i& o-j' 
9ywiye <y$. yf%e/ei 
cj/* 
%p. ,C/. <J</imy. 
ERRATA. 
Page 4, third paragraph : for “ Palaeosyopsos,” read Palaeosyops. 
Page 5, second paragraph : for “ medium,” read median. 
Page 6, fifth paragraph : for “ n,.010,” read M .010. 
Page 7, second paragraph : for “ Ectoganus,” read'Esthonyx. 
Page 11, seventh paragraph : for “ Hyposyus,” read Hipposyus. 
Page 11, tenth-paragraph : for “ four molars,” read three molars. 
Page 12, ninth paragraph : for “ mandibular series,” read preceding species. 
Page 111, eleventh paragraph : for “ sectional,” read'sectorial. 
Page 16, ninth paragraph : for “ normal,” read'dermal. ENGINEER DEPARTMENT, U. S. ARMY. 
GEOGRAPHICAL EXPLORATIONS AND SURVEYS WEST OF THE 
ONE HUNDREDTH MERIDIAN. 
First Lieut. GEO. M. WIIEELER, Corps of Engineers, in charge. 
REPORT 
UPON 
VERTEBRATE FOSSILS 
DISCOVERED IN 
NEW MEXICO, 
WITH 
DESCRIPTIONS OF NEW SPECIES. 
Prof. E. D. COPE, 
PALEONTOLOGIST. 
EXTRACT FROM APPENDIX FF OF THE ANNUAL REPORT OF THE 
CHIEF OF ENGINEERS, 1874. 
WASHINGTON: 
GOVERNMENT PRINTING OFFICE. 
November 28, 1874. [ EXTRACT FROM THE ANNUAL REPORT OF THE CHIEF OF ENGINEERS TO 
THE SECRETARY OF WAR.] 
Office of the Chief of Engineers, 
Washington, I). C., October 20,1874. 
Lieutenant Wheeler has also submitted a report of Prof. E. D. Cope, paleontologist, 
from his camp, on Galinas Creek, in the Rio Grande basin, including a description of 
new species of vertebrate fossils, and of an extensive series of deposits of the Eocene 
age, indicating the existence in earlier geological time of an extensive lake of fresh 
water in that part of New Mexico. 
The collections made and to be made by this special party are likely to prove of un- 
usual interest. 
(See Appendix FF 3.) 
APPENDIX FF 3. 
United States Engineer Office, 
Explorations and Surveys West of the 100th Meridian, 
Washington, D. C., October 15, 1874. 
General: I have the honor to forward herewith a special report received from Prof. 
E. D. Cope, paleontologist to the expedition of this season, embodying some of the 
results of his labors in portions of New Mexico, up to the 27th of September. This 
report contains new and valuable information relative to vertebrate fossil remains. 
Very respectfully, your obedient servant, 
Geo. M. Wheeler, 
Lieutenant of Engineers, in charge. 
Brig. Gen. A. A. Humphreys, 
Chief of Engineers, U. S. Army. 
REPORT ON PALEONTOLOGY. 
REPORT OF PROF. E. D. COPE, PALEONTOLOGIST. 
Camp on Gallinas Creek, September 27, 1874. 
Sir : In accordance with your instructions to forward a report of proceedings, I beg 
leave to state that I returned to this camp from Tierra Auiarilla on the 15th of the 
month, and have remained here ever since. We have been mostly employed in examin- 
ing the bad lands of the Eocene of the divide between the Chama and San Juan Rivers, 
and in collecting the vertebrate fossils which their beds contain. A little time has 
been devoted to the Cretaceous beds forming the rim of the Basin. From the Eocene 
beds, more than seventy-five species of vertebrates have been obtained, many of which 
are new to science, and others are largely illustrated by additional remains. Four 
species of a new order, the Toxodontia, have been discovered, and our knowledge of the 
structure of other peculiar forms enlarged. Interesting relations between the Creta- 
ceous and Tertiary beds have been observed. 
Mr. Shedd has been assisting in making collections and taking his meteorological 
observations at the stated times. 
The health of the party continues good, and we hope to move camp to another point 
ere long. 
Very respectfully, your obedient servant, 
Edw. D. Cope, 
Paleontologist. 
Lieut. Geo. M. Wheeler, 
Corps of Engineers, U. S. A 4 
Notes on the Eocene and Pliocene lacustrine formations of New Mexico, 
INCLUDING DESCRIPTIONS OF CERTAIN NEW SPECIES OF VERTEBRATES, BY PROF. 
E. D. Cope, paleontologist to the expedition. 
One of the results of the examinations made during the field-season of 1874 is the 
discovery of an extensive series of deposits of Eocene age. These indicate the existence, 
during early Tertiary time, of an extensive lake of fresh water in that part of New Mex- 
ico now drained by the tributaries of the Chama River on the east and the San Juan 
River on the west. This lake received the remains of the fauna of its shores and 
other regions adjacent, which have been preserved and obtained by the members of 
the expedition detailed by Lieutenant Wheeler for its investigation, in considerable 
numbers. 
The shore of this lake was formed by rocks of the Cretaceous formation of an age 
near the No. 3 of Meek and Hayden. In approaching it from the east, wo traverse 
the sandstones of Cretaceous No. 1, both horizontal, and tilted at various angles, and 
find No. 2 resting upon it frequently unconformably, and tilted at higher angles, fre- 
quently 45°, sometimes 50°, to the west and southwest, and containing numerous fossils, 
as Inoceramus, etc. The upper sandstones of this formation pass into a brackish or 
fresh-water formation, which includes a bed of lignite, of sometimes 50 feet in thick- 
ness. Above this rests, conformably where seen, a moderate thickness of rather soft 
marine rocks, containing numerous shells, Acephala, Gastropoda, and Cephalopoda, in- 
cluding Oysters, Baculites, and Ammonites resembling A.placenta most, with sharks’ teeth. 
Resting unconformably on these, with a much reduced dip, is a mass of brown and 
reddish sandstones, some 1,500 feet in thickness, inclining perhaps 10° south and 
southeast. These pass continuously into the superincumbent red and gray marls, alter- 
nating with brown and white sandstone of the fossiliferous beds of the Eocene. The 
observed part of these beds is about 1,500 feet in depth. 
A considerable number of species of Vertehrata have been obtained, a large majority 
of which are Mammalia. While it is premature to attempt to determine fully the 
character of the fauna, enough has been ascertained to indicate marked differences 
from that of the Bridger group of Wyoming. It is peculiar iu the entire absence of 
the genus Palceosyopsos, so characteristic of the former, and its replacement by 
Bathmodon, which has never been recorded from the Bridger formation. The abun- 
daut species of Hyrachyus of the Bridger are here represented by a single one of small 
size, which occurs but rarely, while its companion, Hyopsodus, is very rare or wanting. 
While gar-remains are abundant in both, the Amiidce and Siluridce have not yet re- 
Avarded our examinations. The characteristic genera of the New Mexican fauna are 
Bathmodon, Cope; Hipposyus, Leidy ; and Phenacodus, Cope, genera which it shares with 
the Bathmodon bed of the Green River formation of the Bear River Wyoming. There is 
in all respects so close a resemblance between these deposits as to lead to the belief in 
their horizontal identity, and with other reasons, to give to the southern basin a higher 
antiquity than belongs to the celebrated Bridger series. The interesting fact that the 
teeth of six or seA’en species of sharks and one Ostrea have been deposited with the 
mammalian remains indicates that the marine Cretaceous rocks formed the coast-mate- 
rial of this lake, and the earlier period of its deposit is probable on various grounds, to 
be considered at a future time. The facts are all confirmatory of the view already ex- 
pressed by the writer that the population of the Bridger epoch was derived by migration 
from a southern region. 
Perhaps the most important addition to paleontological science obtained during the 
course of the investigation is the discovery of four species of two new genera, Calamo- 
don and Ectoganus of Toxodontia, an order which has not been heretofore identified as 
having existed on the North American continent. 
PART I. 
Ectoganus gliriformis, gen. et sp. nor. 
Char. gen.—This genus rests on a numoer ot remains of the crania of three species, 
including principally teeth, in a good state of preservation, all found in appropriate 
relations by the writer. The teeth include incisors, molars, and premolars, it is believed, 
of both superior and inferior series. 
There are two types of gliriform incisor-teeth, and of one of these in the largest 
species three sizes. In the one, the teeth are elongate, compressed, convex in both direc- 
tions on the anterior ; are convex or angulate in section at the posterior face. In all, 
the enamel is confined to a band on the anterior face, extending more or less on one 
side or the other, the naked dentine extending prominently backward at the middle 
and basal portion of the shaft. 
In the larger size, this portion is subacute behind; in the smaller, obtuse. Teeth of 
this type are of three sizes, the smaller two the most compressed and with narrowest 
enamel. Those of the second type are of one, an intermediate size, and are shorter 
DESCRIPTION OF SPECIES. 5 
than those of the others and less compressed. One of their faces is concave in both 
directions, and is covered with enamel from the apex of the tooth for some distance 
posteriorly. From its terminus on the concave side, the enamel borders retire to the 
sides of the convex front. 
There are three molars of the superior and many of the inferior series available for 
present determination. The superior are all remarkable for the great exposure of their 
external faces as compared with their internal, and the extension of the enamel on the 
outer face of the very thick external root, which is not distinguished from the crown. 
The true molar has three roots, and the crown is longer antero-posteriorly than trans- 
versely. It consists of two transverse tubercular ridges, connected by a medium oblique 
longitudinal ridge. The premolars have two of the roots connate, forming a support 
to the greater part of the crown. The worn surface is in form something like the 
Greek w, the deep emargination being internal. The inferior molars have greater 
antero-posterior than transverse diameters. The enamel is more extended on one side 
than the other, covering the exposed portions of the roots. The grinding surface is 
plane, and has the form of a horizontal ; the limbs being angulate, as in the Greek 2. 
It isimpossible to determine the affinities of this curious genus with the material 
at present in my hands, but it is evidently nearer to the South American Toxodon, 
Owen, and Tgpotherium, Gervais, than anything yet discovered in the North American 
Tertiaries. It is no doubt related to the Anehippodns, Leidv, and TUlotherium Marsh, 
(which Marsh observes may be identical,) but differs from both in many points of the 
dentition. 
Char, specif.—All the incisors are regularly convex in front. The surface of attrition 
of the large ones truncate, of the small ones oblique. The section of the large ones 
near the base is diamond-shaped, with one acute angle truncate and the other rounded. 
There are some shallow grooves on the sides, and on one side a more pronounced longi- 
tudinal shallow angulation. The enamel of these and of all the molars is smooth, and 
there are no cingula on the latter. The transverse crests of the unworn true molars 
support two tubercles, and the inner extremities of the crests of the premolars are pro- 
duced in accordance with the obliqne wearing of the incurved crown in mastication. 
M. 
Length of incisor, largest, type 1 043 
Width of incisor, largest, type 1 013 
Depth of incisor, largest, type 1 01S 
Length of iucisor, medium, type 1 034 
Width of incisor, medium, type 1 006 
Depth of incisor, medium, type 1 014 
Depth (?) of iucisior, last, type 1 009 
Width of incisor, last, type 1 004 
Length of incisor, type 2 031 
Width of incisor, type 2 006 
Diameter of crown of premolar j tra*sver8e 010 
Length of enamel of face externally 013 
Length of enamel of face posteriorly 005 
Length of crown of posterior upper molar 016 
Width of crown of posterior upper molar 012 
Length of crown of posterior lower molar 012 
Width of crown of posterior lower molar 009 
Size about that of a fully-grown hog, (Sus scropha.) 
Portions of several individuals have been found. 
Measurements. 
Calamodon simplex, gen. et sp. nor. 
Char, gen.—Molar teeth subcylindric, prismatic, rootless; the crown only distinguished 
by its investiture of enamel, which exhibits a weak marginal inflection for a portion 
of the length. Enamel extending in a band on one or both sides of the tooth to the 
base. Incisors rodent-like, curved, with a band of enamel on the anterior face, and 
obliquely-truucate extremity. 
A number of specimens, probably representing this genus, have been found, and I 
select as typical those of an individual in which the molar and incisor teeth occurred 
together. The form is evidently allied to Ectoganns, as the close resemblance of the 
incisor teeth demonstrates, but the molars are of a much more simple type than any- 
thing yet discovered in this group, imitating superficially those of some Edentata. 
Char, specif.—Molar (? superior) longitudinally bent, the convex (outer) face covered 
with enamel to the base. Enamel extending a much shorter distance on the inner 
face, and soon worn through by attrition on one of the other faces. Section of the 
base of crown a subquadrate oval. A slight inflection of enamel on the inner and a 6 
still weaker one on the (l)posterior border of the triturating face. Enamel with slight 
longitudinal ridges. Incisor much curved, strongly convex in transverse section, the 
enamel obscurely longitudinally ridged on both sides near the border. Section of one 
side slightly concave. 
These and other specimens indicate an animal at least as large as the American tapir. 
Measurements. 
M. 
Length of a molar 042 
Diameter of the same 015 
Diameter of incisor, transverse 019 
CaI.AMODON ATtCAMCENUS, Sp. UOV. 
This Troxodont is represented by a portion of the skeleton of a specimen including sev-. 
era! teeth, and most probably by portions of another, which includes a large and per- 
fect inferior incisior-tootli. The former displays the alveoli for molars and incisors, 
showing the one-rooted character of those of the lower and the deep implantation 
of the incisor below the antepenultimate molar. The number of molars indicated by 
the ramus is five, the anterior in close contact with the single large incisor. The mo- 
lars are subquadrate'in section, the last a little longer than broad. The only one in 
which the crown is preserved exhibits a short crown, with its inferior enamel border 
notched on two, and oblique on two sides, and the external layer of the root swollen 
above it all round. The summit of the crown is worn, and is divided subequally by a 
transverse, rather shallow, groove. One division of the crown exhibits two dentinal 
areas in transverse line, the other three small ones in a curved line. The extremity of 
the curved incisor is rodent-like, and regularly convex on the anterior face and entirely 
smooth. The posterior or grinding face is convex in cross-section. 
A large lower incisor of another individual is about five inches in length and one and 
a halt in depth, without the increase of elevation of the superior or interior edge, as is 
seen in Ectoganus glirifonnis. This edge is obtusely rounded, and instead of being 
obliquely leveled to meet the masticatory surface of the extremity, is abruptly trun- 
cate, the masticating face turning off at one side of the shaft. The enamel is smooth 
and of equal width and convexity throughout. 
Measurements. 
M. 
Elevation of crown of molar 013 
Length of crown of molar 015 
Width of crown of molar 013 
Diameter of incisor™. 010 from tip 013 
Length of series of live molars 090 
Depth of jaw at third molar 055 
Thickness of jaw at third molar 035 
Calamodon novomkhicanus, sp. nov. 
Represented by a superior incisor-tooth of a species of smaller size than either of 
those already described, and differing in various respects from those of the C. simplex, 
of which a due specimen has been obtained since it was first described. Both anterior 
and posterior edges are protected by a convex band of enamel; and the triturating sur- 
face is trail verse in the direction of the depth, and oblique in that of the width. The shaft 
increases in depth toward the root and is longitudinally concave on one face and con- 
vex on the other. The enamel bands are most extended on the convex face, and unite 
on that side round the triturating face and present an abrupt emargination on the 
middle of their convex border. The other, being formed of dentine only, is deeply 
worn by attrition. 
Measurements. 
M. 
Length of fragment 038 
Depth at fracture 018 
Depth at grinding face Oil 
Width at grinding face 009 
This species differs from the supposed C. simplex in this incisor in other respects than 
in the smaller size. The latter is concave on both sides, and on the lower border ; the 
former convex on one side, and on the lower border. 
Estiionyx bisulcatus, gen. et sp. nov. 
Char. gen. (?).—Incisors of two forms; the inferior subgliriform, but not growing 
from persistent pulps ; the enamel covering a long and narrow external vertical face, 
and terminating above the alveolus, thus distinguishing crown and root. The other 
form of (?)incisor with the apex encased in enamel, but extending much farther on the 7 
outer than the inner side; the crown compressed, not wider than the root. Molars 
supporting two V’s with rounded apices directed outward, the posterior soon wearing 
into a triangle lower than the anterior. The anterior elevated and transverse only 
distinguished from a triangle by a notch on the inner side. Last lower molar with 
this anterior transverse triangle, a diagonal ridge and a heel with raised border. 
The type of this genus is Ectoganus hisulcatus, Cope, and a second species is E. burmeis- 
terii, Cope. It differs from Ectoganus as well as from Anchippodus in the far less gliri- 
form character of the incisor teeth, which may be compared with the extremities of the 
slender fingers of some monkeys with narrow nails. 
Char. specif.—A species about the size of the Capyhara is represented by the greater part 
of the dentition of the lower jaw, which includes representatives of both kinds of incis- 
ors already described under the characters of the genus. The rodent-like form is less typi- 
cal of the genus than in the E. gliriformis in being rather shorter and furnished w ith a 
less extensive external enamel-plate. The dentinal column projects well internally, 
giving the tooth i regularly oval section. The incisor of the second form has the in 
terual as wrell as the external enamel-face, and the former possesses a longitudinal an- 
gle bounding its concavity. The grinding-face of the molars and some of the premo- 
lars is go -shaped as in the other species, but the anterior limb of the figure is much 
thickened on the inner face, so as to have a triangular form, the base being inward. 
This base is notched by a second groove of that side of the tooth, which interruption 
is obliterated by prolonged attrition. This portion of the crown is elevated above the 
posterior, in consequence of the more rapid removal of the latter by trituration. The 
large internal and external grooves continue nearly to the base of the crown, as in the 
larger species. The last inferior molar is longer than the others, aud is three-lobed, 
forming by its base nearly an isoceles triangle. The heel is formed by the backward 
production of the posterior convexity of the co , the central line of the figure forming 
a diagonal ridge across the middle of the tooth. 
The mandibular ramus is of a deep compressed form. 
M. 
Length of three consecutive molars 0250 
Length of last two molars i 0210 
Length of penultimate molar , 0084 
Width of penultimate molar 0062 
Length of last molar. 0112 
Width of last molar 0070 
Length of incisor, second form 0250 
Diameter of incisor, second form 0050 
Diameter of incisor, first form, transverse 0030 
Diameter of incisor, first form, antero-posterior 0070 
Estiionyx burmkisterii, sp. nov. 
A species more nearly allied to the E. hisulcatus than to the type of the genus is 
represented by a portion of the right mandibular ramus, with the last molar tooth in 
perfect preservation. While the jaw is of depth similar to that of the E. bisulcatus, it 
is more slender in its proportions. The molar, also, while of nearly the same length, is 
relatively narrower, especially in its anterior portion. The crown of this tooth is worn 
in the specimen, and the anterior portion is elevated above the posterior, aud displays 
a trace of the notch of the inner margin already observed in the species last described. 
The composiiion of the tooth is similar in other respects. No ciugular; enamel 
smooth. 
Measurements. 
Measurements. 
M. 
Length of last lower molar -009 
Length of last lower molar from anterior tubercles 0060 
$ anteriorly 0050 
} posteriorly 0025 
Depth of ramus at last molar *0240 
This species is dedicated to Prof. Hermann Burmeister, director of the museum of 
Buenos Ayres, who has studied the group of Toxodontidw, and given us an excellent 
account of their osteology. 
Estiionyx ackr, *p. nov. 
Char, specif.—Established on a portion of the lower jaw, in which the last four pre- 
molars remain. They resemble those of the species already named, except in the ante- 
rior one of the series. This tooth in E. acer assumes the form of a premolar, the 
posterior V becoming a curved median cutting edge, and the anterior V opening into a 
crescentoid section ; it rises to an acuminate apex, having thus a rather sectorial char- 
acter. In the last three molars, there is a small tubercle at the inner base of the pos- 
terior limb of the anterior V. Posterior Vmuch lower; enamel smooth. 8 
Measurements. 
M. 
Length of four last molars 035 
Length of three last molars 026 
Length of penultimate molars 008 
Width of penultimate molars 005 
Length of last molar Oil 
Width of last molar 005 
Depth of jaw at last molar 020 
This species differs from the E. hisulcatus in the modified form of the last premolar; 
in the latter, it is relatively larger and more like the true molars. The last molar of 
E. acer is more like that of the E.burmeisterii, but the mandibular ramus of that species 
is relatively much deeper and similar to that of E. hisulcatus. 
Esthonyx miticulus, sp. nov. 
Represented by portions of mandibular rami of three or four individuals of much 
smaller size than any of those referred to the species already described. There are 
represented two premolars and three molars; other teeth are lost. The molars differ 
from those of the three species named in lacking the notch or groove on the iuner side 
of the anterior triangle of the crown, which constitutes it a V in those species, giving 
the worn surface a more simply sigmoid form ; the anterior portion is, moreover, not 
materially more elevated than the posterior. The last molar has a large heel, an inner 
and two anterior tubercles when little worn. The premolars preserved are each two- 
rooted, the last is like the correpouding one in E. acer, the penultimate without heel or 
inner tubercles. 
M 
Length of three true molars, (No. 1) 0120 
•Length of two last premolars, (No. 2) 0064 
Length of first true molar, (No. 1) 0040 
Width of first true molar, (No. 1) 0030 
Depth of ramus at first true molar, (No. 1) 0080 
The worn surfaces of the first and second true molars are much like those of the cor- 
responding teeth of Menotherium, Cope. That genus differs in the reduced form of the 
last inferior molar and in the premolars. 
Meniscotherium chamense, gen. et sp. nov. 
Char. gen.—Molars three, with two continuous external crescents and two internal 
tubercles, except on the posterior, where there is but one, the anterior conic tubercle. 
The posterior tubercles on the other molars crescentoid in section. A well-developed 
crescent between the anterior tubercle and anterior crescent, and an oblique crest 
extending from the latter to the adjacent horn of the posterior inner tubercle. Two 
• external crescents on the last premolar. 
This genus presents a curious combination in the structure of its molars of the 
.character of Palceosyops, llyopotamus, and Hipposyus. It is exceptional among the 
ungulates of the same fauna in the number of crescents of the molars. 
Char, specif.—Last molar with the oblique inner posterior crest terminating at the 
'posterior margin of the crown. Prominent external ribs at the point of connection of 
the external crescents of the crown. No cingula ; enamel entirely smooth. 
Measurements. 
M. 
Length (externally) of last four molars 029 
Length of true molars 022 
Length of penultimate 009 
Width of penultimate 010 
This animal was about the size of the raccoon, and probably had the habits of tha 
tapirs. 
Batiimodon simus, sp. tiov. 
Represented by the remains of a great number of individuals, including all parts of 
the skeleton, dentition, &c., but especially by one of the most complete of these, which 
possesses, among other portions, the premaxillary bones. These indicate a species very 
distinct from the B. radians, Cope, and one approaching the Hetalophodon armatus in the 
-structure of the molar teeth. 
The canine teeth have cylindric roots and trihedral crowns, the section of the latter 
forming a nearly equilateral spherical triangle. The crown of the inferior canines are 
shorter, and have one concave side. The superior molars support two crests, which are 
Measurements. 9 
nearly parallel on the single and last tooth of this type. The posterior crest is com- 
posed of two portions, the posterior conic and the anterior flatter, and which becomes 
the external posterior crescent on the penultimate molar. The anterior ciugular crest 
is very well developed on the last lower molar. 
The premaxillary bone is short and stout, and descends steeply from an elevated 
front, presenting its three teeth downward. The canine follows closely from 
vated rib on the side of the face. Behind it is a considerable diastema. The humerus 
is a very stout bone, and the femur is rather slight in comparison with it. 
M. 
Length of bases of last three molars 083 
Length of basis of last molar 026 
Width of basis of last molar 035 
Diameter of canine at base 025 
Length of penultimate inferior molar 030 
Width of penultimate inferior molar 021 
Individuals of larger size than the above are more common. Measurements of one 
of these are: 
M, 
Length of last superior molar 032 
Width of last superior molar 043 
Diameter of crown of canine, (another species) 030 
This is the especially characteristic large mammal of this fauna, and must have 
existed in herds. 
Bathmodon molestus, sp. nor. 
Established on remains of one species and probably respresented by those of others 
in possession of the expedition. The teeth differ in several important respects from 
those of B. radians and B. simus. Thus the canine is quite compressed in the coronal 
portion, and is narrow triangular in section, the narrow base of the triangle being con- 
cave ; that is, the section of a strong groove, which is bounded by a sharp edge on each 
side. The edge proper of the crown is also duplicated by a ridge of the enamel, 
which joins it at an acute angle. The last upper molar is characteristic in its wide 
crown, the posterior usually transverse crest being curved so as to represent the seg- 
ment of a circle, the convexity posterior. The ramus of the lower jaw is very sleu- 
der. The posterior inferior molar is large, and has subequal transverse crests. The 
posterior cingulum, which descends from the external angle, is moderately developed 
on both of the crests. 
In a young specimen of this or au allied species of Bathmodon, the deciduous tooth 
which is replaced by the last piemolar has two external crescents; an interesting 
point of resemblance to the Berissodactyle ungulates. 
Measurements. 
M. 
Width of anterior crest of last inferior molar .023 
Width of anterior crest of superior molar 039 
Length of superior molar 029 
Antero-posterior diameter of crown of canine 022 
Transverse diameter of crown of canine 013 
Depth of mandible at last lower molar .050 
BaTIIMODON LOMAS, 8/>. VOV. 
The very numerous remains of the genus Bathmodon obtained are referrible to several 
species, as indicated especially by the teeth. The present form is characterized among 
other points by the form of the last inferior molar. The anterior crest is much more 
elevated than the posterior, with its inner apex almost a cone, with anterior, thick, 
revolute border. The usual oblique cingulum descends from the outer apex forward. 
The longitudinal ridge connecting the crests is low but distinct, while the posterior 
ciugular ridge is remarkably large. This, which constitutes one of the specific marks, 
is extended horizontally so as to form a broad ledge, whose border is a segment of a 
circle. Enamel roughened with five ridges on all the external surfaces. Tooth well 
worn by prolonged use. 
Measurements. 
Measurements. 
M. 
Length of crown 041 
Width of crown anteriorly 027 
Width of posterior crest 022 
Elevation of posterior crest Oil 
Elevation of anterior crest 024 10 
BaTIIMODON EEEPIIANTOrUS, Sp. 110V. 
The most abundant species of the New Mexican Eocene formation, and of the largest 
size, exceeding in this respect' both the B. sirmis and B. molestus. I describe at present the 
last molars of both superior and inferior series. The former is a transverse oval, slightly 
swollen on the posterior border external to the middle point. The two crests are par- 
allel, the anterior as usual curving round to the inner extremity o the shorter poste- 
rior, and leaving a wide interval between them. The posterior is not divided, but is 
elevated at the extremities. Anterior cingulum strong, posterior obsolete, excepting on 
the external border, where it sends a low ridge to the elevated extremity of the anterior 
crest. Exteroanterior to this ridge is a shallow fossa. Enamel very slightly rugose. 
The posterior low er molar exhibits a great disparity of elevation of the crests, the 
anterior being high, and terminating ou the inner side in an elevated cone. The con- 
necting ridge is low, and there is only a trace of a descending posterior cingulum on 
the posterior crest. 
M. 
Width of last superior molar 040 
Length of last superior molar 030 
Length of last inferior molar 039 
Width of last inferior molar 026 
Elevation of posterior crest of inferior molar 015 
Elevation of anterior crest of inferior molar 025 
A remarkably fine skeleton of a species of this genus, discovered !>v my friend and 
assistant, William G. Shedd, exhibits characters heretofore only inf i enrial, and dem- 
onstrates the correctness of a number of positions heretofore base ! on i few fragment- 
ary bones. The feet exhibit proboscidian characters throughout. They are very short 
and plantigrade, and there are five digits on the hind foot. The ale riHUin is recurved 
inward, and the astragalus flat above. The navicular is transvers ■ and very thin, 
while the cuboid is subequilateral. The metatarsals are short, and the phalanges much 
wider than long. The cranium remarkably resembles that of a carnivorous animal in 
its massive expanded zygomas and huge canine tusks. It differs remarkably from this 
type, aud shows its affinity to Uintatherium in the broad plane of the upper crauial wall, 
with overhanging marginal crests for the attachment and protection of the temporal 
and neck muscles. These crests do not support horns. The muzzle is contracted at 
the diastema, thus rendering more prominent the ridges which mark the position of 
the alveoli of the tusks. The latter are directed downward, giving the profile the 
pick-ax-like form of that of Uintatherium, though more robust in its proportions than 
the latter. The length of this skull is 19 inches ; the width at the zygomas 13. 
Measurements. 
Phenacodus prim.evus, Cope.* 
Char. gen.—The genus Phenacodus was first recognized by the writer in a posterior 
inferior molar of a mammal of about the size of a hog, of unknown affinities, which 
was named P. primcevus. Specimens of the same species, embracing the dentition of 
both jaws, having been procured in the Eocene of New Mexico, I am prepared to add 
to the characters of the genus. 
There are three molars in each jaw, and the specimens include two premolars, which 
form a continuous series, as in Achamodon. There are four principal tubercles on the 
inferior molars and sometimes a third small one between the posterior pair, always on 
the last one, which is, however, not largely developed. The first inferior premolar 
presents a broad heel, a double medium tubercle, and an anterior tubercle, (in P. pri- 
nieevus.) The crowns of the superior molars are low and broad, and support numerous 
tubercles; these are low aud vary in number, but there are two near the external bor- 
der which are quite constant. They have general resemblances to those of hogs, bears, 
and monkeys. The first true molar is broader than long, and there are no diastemata 
between it and the premolars, or between the latter, which are quadri-, and tri-cuspid, 
respectively. The forms of these teeth are entirely different from those of the corre- 
sponding teeth in Elotherium. 
Char, specif.—The posterior molar of the left side is wide in front and regularly oval 
in posterior outline, and has two equal anterior and three uuequal posterior tubercles. 
One of the posteriors is situated near the middle of the outer side, and is separated from 
the adjacent anterior by a deep groove. The.corresponding iuner tubercle is more pos- 
terior; anterior tubercles low, trihedral, and connected by a shelf-like cingulum across 
the front of the tooth ; rudimental cingula on outer side of crown. The penultimate 
molar has three tubercles on the posterior border; aud a deep tissue, corresponding to 
that of the last molar, separates one of them from the anterior tubercle. 
* Paleontological Bulletin, No. 17, p. 3, October 25, 1873. 11 
f M. 
Length of last molar 015 
Width $ anteriorly 011 
1 ) between two posterior tubercles 005 
Elevation of anterior cusp from base 008 
Width of penultimate molar behind 010 
From the same locality as the preceding species. 
Phenacodus omnivokuSj sp. nov. 
Superior molar with low and broad tubercular crown, with outline of base parallelo- 
grammic, with one end oblique; the oblique end with two principal low tubercles, 
which form the extremities of two series of similar ones, some of which arise from 
the strong cingulum which forms part of the summit of the crown. 
Char.—Molar without cingulum on the (?) outer side only ; elewhere very strong and 
cremate, at one point rising into a stout, low tubercle. The largest tubercle is near 
this,.on the inner summit of the crown, and is connected with the larger outer by a 
low, broad tubercle. A smaller one intervenes between the cingular tubercle aud the 
smaller external. The outer tubercles low and broad, a smaller one opposite the inter- 
nal between them in the position of a cingulum. Enamel coarsely rugose. 
Measurements. 
H. 
Transverse diameter 014 
Longitudinal 010 
Distance between apices of inner and outer tubercles 007 
Elevation of cingulum 004 
Elevation of outer cusp 005 
The tooth described is about the size of the posterior inferior molar of the black 
bear, (Ursus americanus.) 
Phenacodus sulcatus, sp. nov. 
Represented especially by the molar tooth corresponding to that above described 
under the head of P. omnivorus, in good preservation. It is a species considerably less 
than half the size of the one just named, aud presents several important differences of 
structure. Of the two outer tubercles, one is very small, aud there is a third adjacent 
to the larger, produced by the enlargement of the cingulum. As in P. omnivorus, the 
cingulum extends entirely round the remainder of the crown, and is tubercular on the 
side of the least outer tubercle. The inner tubercle is connected with the larger outer 
by au intermediate of elongate form, so that the series when worn down resembles the 
transverse ridge of the superior molar of Hyposijus, and which is separated by a groove 
from the cingular ridge on each side. 
Measurements. 
M. 
Transverse diameter .008 
Longitudinal diameter 006 
Distance between apices of inner and outer tubercles 004 
Elevation of cingulum 002 
Elevation of outer cusp 003 
Size similar to that of the corresponding tooth of a Coati. 
OxytENA i.upina, gen. et sp. nov. 
Represented by a portion of the cranium, which includes the greater part of the denti- 
tion. The generic characters are, three premolars and four molars above and below ; 
lower premolars with anterior cone and posterior cutting heel; last premolar and all 
the molars of the superior series with an internal heel; the last molar transverse ; first 
and second upper molars with an anterior cone and posterior cutting lobe; the penul- 
timate with two anterior acute cones, the posterior forming a sectorial edge with the 
posterior lobe; last superior molar trenchant. 
Mandibular dentition, I., 0; C., 1; P. M., 3; M., 3; the caniue teeth directed forward 
and upward without intervening incisors. First premolar one-rooted; second aud 
third consisting of an anterior elevated cone, aud posterior heel, which is elevated in 
the middle. 
The first true molar is nearly similar, with the posterior tubercle sharp edged. Last 
two molars with an anterior elevated portion and small low heel; the former consisting 
of three acute tubercles, of which the largest or interior forms with the anterior a sec- 
torial blade oblique to the axis of the mandibular bone. 
Measurements. 12 
This genus has one less molar with double median than Prototomns. It is one 
of the flat-clawed group, of which two forms have already been described, Mesonyx, 
Cope, and Synoplotherium, Cope, which present in their dentition a nearer resemblance 
to the genus Hycenodon than to any other of later age. It differs from both the genera 
named in having only six molar teeth, and the triangular type of inferior sectorial 
teeth has not yet been obtained among them. The O. forcipata is the larger species ; 
the smallest one described by me is the Oxya'na morsitans. In Stypolophus brevicalca- 
ratus, I find three sectorials of the form described instead of two only. 
Char, specif.—The posterior cutting lobes of molars 1 and 2 elevated and rather obtuse, 
that of molar 3 lower and more acute. Molar 2 has a well-marked anterior tubercle; 
molar 4 cousists of an outer cutting edge and inner cone. The inner tubercle of molar 3 
is smaller than in the three teeth preceding. F.rst lower preiuolar well developed with 
one root. Enamel of all the teeth, especially of the canines, rugose. 
This species is allied to those of the genus Ptcrodon. 
M. 
Length of four posterior superior molars U55 
Length of first, true molar 016 
Width of first true molar 015 
Lengt h of second true molar 016 
Width of third (transverse) molar 
Length of five anterior inferior molars 054 
This species is intermediate in size between the 0. forcipata and O. morsitans. The 
penultimate inferior molar differs from that of both these species in the much weaker 
development of the internal lateral tubercle and more obtuse anterior tubercle; in 
O. forcipata the blade is continued on the front of this tubercle. 
Two specimens embracing five series of teeth have been examined by the writer ; the 
measurements given are those of the smaller. 
OxyyEna morsitans, sp. nov. 
The genus of flesh-eating mammals, described in 1872 under the name of Stypolophns, 
presents a type of dentition which is further illustrated by the present addition of new 
species much larger than any hitherto known to possess it. Those described are in 
the order of size : S. insectivorus, S. pungens, and S. brevicalcaratus, Cope. The present 
new species is twice the bulk of the last. It is represented by broken mandibles with 
molars and canines of two specimens, and part of the maxillary dentition of a third. 
The molar, which is typical of the genus, in its subtriangular basis supporting three 
elevated cnsps, and a short heel, is evidently functionally the sectorial, what- 
ever its homological relations may be. In the present instance, the inner posterior 
cusp is much reduced, while there is a small additional cusp on the front of the ante- 
rior near its basis. The trihedral outer posterior forms a cutting edge with the large 
outer auterior, which is produced forward. A posterior molar exhibits a correspond- 
ing tricuspidate portion, and a more elongate heel, with acute circumference. In a 
premolar, the posterior heel becomes trenchant, and median. The canine is very stout 
and compressed at basis. The enamel in all the teeth is more or less rugose. 
Measurements. 
Measurement8. 
M. 
Length of base of crown of sectorial tooth 014 
Width of base of crown of sectorial tooth 009 
Elevation of principal cusps 015 
Elevation of inner posterior cnsps 007 
Length of basis of posterior molar 012 
Width of basis of posterior molar 007 
Length of heel of posterior molar 005 
Elevation of principal cusps Oil 
Elevation of anterior cnsps OOG 
Long diameter of canine at base 018 
The maxillary series belongs to a still larger animal. The sectorial presents the 
same form as that of the mandibular series, and is more robust in form than in existing 
Carnivora. The section of the middle crests is very convex on the inner side, so that the 
shear is oblique. The heel is small and low. The premolar preceding has a large, 
broad heel. In another premolar, the heel supports a median crest, while the anterior 
part of the crown is a slightly-compressed cone, with a small tubercle at the anterior 
base. Other specimens indicate that tnis species lacks the inferior incisor teeth. 
forcipata, sp. nov. 
Char, specif.—Mandibular rami robust and deep, with the symphysis short, and the 
chin contracted. The canine tooth forms a vertical oval in section. The first one- 13 
rooted premolar is a stout tooth ; there is no anterior basal tubercle on the second and 
third premolars, but a distinct one on the first true molar. There is a small tubercle 
at the base of the anterior lobe of the last or second sectorial molar. This tooth is 
larger than the penultimate. The enamel of all the teeth is quite rugose, although 
they are well worn by use. 
Corresponding characters are exhibited by four specimens of this species, one of 
which includes portions of the upper jaw. All the bones are particularly massive, 
and there is a high parietal crest, a fair indication of the size of the temporal muscles. 
Additional specimens of the Oxywna morsitans, Cope, show that it differs in the 
reduced size of the sectorial molars, and the very small first premolar, which is quite 
rudimeutal. 
Measurements. 
M. 
Length of inferior dental series 103 
Depth of ramus at last molar 040 
Depth of ramus at second premolar 030 
Diameter of canine tooth 019 
Length of premolar series 035 
Length of base of penultimate molar - 016 
Length of base of last molar .019 
Width of base of last molar 012 
Elevation of crown of last molar 019 
Length of superior last molar 020 
Width of superior last molar 013 
This animal differs in specific characters from the Wyoming carnivores, already re- 
ferred to, in the greater robustness of all its parts. From Synoplotherium lanius, it also 
differs in the regular increase backward in the size of the molars. In the Wyoming 
species the penultimate is largest in the lower jaw. 
The fragments of the Oxyana forcipata are as large as corresponding parts of the 
jaguar. 
PaciiyvEXA 08Sifraga, gen. et sp. nov. 
Char. gen.—Established on a single superior molar tooth of a large carnivore, ap- 
parently allied to the group of flat-clawed Carnivora. It is either the last premolar 
or first true molar. It is characterized by the absence of the cutting edge seen in the 
allied genera, and its replacement by a conic tubercle. 
The principal lobe is also a cone, and the inner one a perfect cone, a little less ele- 
vated than the principal one. 
Char, specif.—Crown with well-developed anterior and posterior basal tubercles; 
no ciuguli, either internal or external. Enamel slightly rugose. 
Measurements. 
M. 
Length of crown 020 
Width of crown 018 
Elevation of anterior basal tubercle .006 
Elevation of central cone Oil 
Elevation of interior cone 010 
This is the largest carnivore yet observed in this formation, and of peculiar charac- 
ter; its structure indicating a diet not purely carnivorous. 
Prototomus viverrinus, gen. et sp. nov. 
Char. gen.—Three true molars in the maxillary bone ; premolars compressed, the last 
of the upper series triangular in form ; each angle enlarged ; the center of the crowu 
with a compressed conic tubercle. First and second true molars triangular, with a 
tubercle at each angle, and two adjacent cones in the center. The tubercle of the pos- 
terior angle forms a slight sectional edge with the posterior of the central pair. Last 
(third molar) transverse, with a median cone. Supposed mandible with the posterior 
two molars tubercular; the anterior tubercles similar to the posterior. 
This genus is evidently allied to the Viverridce, differing from Viverra, so far as known, 
in the simple character of the last two inferior molars. From Limnocyon it differs, ac- 
cording to Professor Marsh’s descriptions, in possessing three instead of two superior 
true molars, or, if we include with these the last premolar, as does Professor Marsh, 
four instead of three. According to Professor Marsh, the tubercular molars in his 
Vulpavus are generally similar to those of the existing genus Canis. i'rofofomas pre- 
sents the number of suuerior molars seen in Amphicyon. 14 
Char, specif.—The P. viverrinus is established on a considerable part of the cranium 
and skeleton of one individual in good preservation. The last upper premolar is tri- 
radiate, having concave and subequal sides. The first molar is as broad as long, and 
is triangular, presenting a right angle outward and forward. 
The second molar is broader than long, and presents au acute tubercle on the ante- 
rior border between the inner and anterior median cones. There is a tubercle at 
the inner and outer extremities of the base of the last molar. No cingulum on the pos- 
terior or outer sides of the last premolar. External cones of the last two inferior mo- 
lars subcrescentic in section ; anterior inner obsolete ; posterior inner prominent. 
M. 
Length of last five molars 0250 
Length of true-molar series 0135 
Length of last premolar 0060 
Width of last premolar 0050 
Length of penultimate molar 0050 
Width of penultimate molar 0068 
Width of last molar 0047 
Length of last two inferior molars 0090 
About the size of the domestic cat. 
P'rototomus insidiosus, sp. nov. 
Represented in the collections of the survey by parts of the maxillary bone and both 
mandibular rami with teeth. The species is much less than the preceding, and differs 
materially in the forms of the teeth. The two anterior tubercles of the tubercular 
molars are similar and approximated; the posterior slightly divergent, and on the last 
tooth inclosing a third of small size. The last premolar has a broad heel and stout 
anterior cone, but no anterior tubercle. The tooth immediately preceding is much 
smaller, and also possesses a heel. The mandibular ramus is particularly slender, and 
the angle is not inflected. 
Measurements. 
Measurements. 
M. 
Length of last two inferior molars 0060 
Length of last molar 0034 
Width of last inferior molar ., 0020 
Depth of ramus at last inferior molar 0045 
Leugth of last premolar 0030 
Elevation of last premolar.. 0028 
Prototom us jarrovii, sp. nov. 
This Carnivore is of considerably larger proportions than either of the preceding. It 
is readily reeoguized as pertaining to the same genus by the identical form of the last 
two inferior molars, which are quite different from the corresponding ones in Oxycena 
and other genera. These indeed, with the portion of the mandibular ramus which sup- 
ports them, are the only well-preserved remains of this animal as yet in our possession. 
They indicate an animal of the size of the gray fox. In the last molar, the inner ante- 
rior tubercle is double, though low and obtuse. It differs from that in the species last 
enumerated in the presence of only two tubercles on the posterior portion of the crown 
instead of three, one being terminal and the other on the middle of the outer side. 
There are but two on the posterior eud of the penultimate tooth, and all are low and 
unconnected excepting by the distinct rim of the crown. The center of the crown is 
thus concave. The rim is interrupted by notches between the tubercles on the outer 
side. No cingulum on inner, a weak one on outer side. Enamel smooth. 
The form of the molars is rather stout, and the ramus is thick and not deep, and 
with broad, simple, lower border below the molars. 
Measurements. 
M. 
Length of last lower molar 0070 
Wldthl posteriorly 0020 
Width of penultimate behind 0050 
Elevation of anterior cusp of last 0030 
Depth of ramus at last molar 0140 
This species is dedicated to my friend Henry C. Yarrow, M. D., to whom was com- 
mitted the charge of that party of the survey to which I was attached, and to whose 
zeal in the cause of the natural sciences the success of the special expedition is largely 
due. 15 
Limnocyon protenus, sp. nov. 
A civet-like Carnivore represented by one entire and a portion of the other mandibu- 
lar ramus, with teeth well preserved, agrees in generic characters with the species 
referred by Professor Marsh to his genus Limnocyon, but differs from them all iu its 
superior size. The molars are f, but the first molar is like the premolars of the Ca- 
nidee, except in a slight widening of its posterior basis by the development of a broad 
cingulum on the inner side and round the basal lobe behind. From this point it ex- 
tends forward on the outer side to the beginning of the auterior basal lobe, and there 
ceases. The second molar has the anterior portion elevated, supporting three cusps and 
a large heel, wi h lateral and sub-median cutting edges. The last molar is smaller, 
elongate, oval, and two-rooted, with marginal posterior, intermarginal external, and 
two anterior tubercles, of which the inner is bifid. The ramus is slender, and the 
symphysis elongate. The angle is not incurved. First premolars one-rooted. 
M. 
Length of dental scries 0680 
Length of four premolars 0340 
Length of first molar 0105 
Length of second molar 0100 
Width of second molar 0055 
Length of third molar 0080 
Width of third molar in front 0040 
Depth of ramus at third premolar 0130 
Depth of ramus at last molar 0150 
Alligator ciiamknsis, sp. nov. 
Represented by portions of the mandibular arch of a small crocodilian resembling in 
some respects the A. heterodon of the Wyoming beds. The posterior teeth have the same 
short, expanded, sessile, bean-shaped crowns, with a median longitudinal ridge, and 
more delicate 1 in s radiating close together from it to the border of the crown. The 
anterior teeth differ in being cylindric instead of compressed. There is a large canine 
preceded and followed by teeth of much smaller size. 
Measurements. 
Measurements. 
M. 
Length of symphysis 019 
Length of alveoli of six teeth from symphysis 022 
Width of ramus just behind symphysis 010 
Long diameter of posterior tooth 005 
The specimens selected as type is one of the smallest. The surface of the bones is 
roughened with pits. 
PlASTOMKNUS LACH ItVMALIS, 8j). 110V. 
The largest sp< cies of the genus, and abundantly represented in the Eocene of New 
Mexico. The costal bones are rather finely punctate, the posterior as well as the an- 
terior. The anterior costal bones are crossed by numerous ridges from side to side 
obliquely; the obliquity increasing posteriorly. On the posterior bones, they are 
broken into vertical bars, separated by considerable intervals, and of linear form. 
The posterior costa Is reach a thickness of 0n'.00G and a width of 0m.025. 
The jutting of he posterior part of the carapace distinguishes this species from the 
P. cede mins. 
PART II. 
In addition to the investigations pursued in the regions already indicated, and of 
which some of the new species have been described, it may be stated that a careful 
examination was made of the extensive lacustrine deposits in the valley of the Rio 
Grande. 
These deposits are supposed to commence to the northward of Taos, N. Mex., and 
continue to an unknown distance southward, certainly at least fifty miles beyond 
Santa F<5, and occupy that portion of the valley between the Rocky Mountains iu the 
east and the Jemez range in the west, and have been stated as late Tertiary, but with- 
out special determination or co-ordination with the other known lacustrine formations 
of this continent.* 
Abundant material having been obtained by the party, it is easy to determine the 
fauna, whose remains are entombed in it, to be a part of that already described by Dr. 
Leidy and the writer as occurring in Dakota and Colorado under the name of Pliocene. 
# The new species described from the valley of the Rio Grande were discovered from 
August 20 to September 1, 1874. 16 
This conclusion is indicated by the presence of the genera Hippotherium, Protohippus, 
Procamelus, Cosoryx, and Meryckippus, and known Pliocene species of other genera, 
among which may be mentioned Canis, Aceratherium, &c. In addition to species 
already known, a number new to science were obtained, of some of which descriptions 
are hei'e given. 
Martes nambianus, sp. nov. 
Represented by a mandibular ramus, which supports three teeth. The anterior blade 
of the sectorial is rather obtuse. 
The first premolar is one-rooted ; the second and third are without posterior coronal 
lobes, but exhibit small basal lobes, both anterior and posterior. The anterior of the 
second is rather elevated, and the entire crown is directed obliquely forward. Canine 
compressed; mental foramiua below the second and third premolars. 
Measurements. 
M. 
Length of three premolars 006 
Elevation of anterior lobe of sectorial 002 
Depth of ramus at anterior lobe of sectorial 003 
This species is of smaller size than the M. muatelinus, Cope, and the sectorial tooth 
less elevated and trenchant. 
COSORYX RAMOSU8, sp. nov. 
Char. gen.—Inferior molars prismatic, f; the premolars all sectorial, last with 
short branch-crests. Molars with basal iutercolumuar tubercles. Horns superciliary, 
solid, branched. This genus was iudicated by Dr. Leidy from a horn of the species 
known to him, the Cosoryx furcatus, from the Pliocene beds of the Niobrara. The same 
or a similar species has left abundant remains in the Santa F6 marls, and, in connec- 
tion with the more numerous C. ramosus, has enabled me to determine the dental and 
other characters of the genus. After a careful examination of the horns of these spe- 
cies in my possession, those of eighteen individuals (at least I find that of ten where 
the basal portion is preserved) the beam has been broken off and reunited by anchy- 
losis in six. In most of these the spot is marked by a ring of exostosed tuberosities, 
like those constituting the burr of the deer’s horn. On a specimen of this character, 
pertaining to a third species, Professor Leidy based his Cervns warrenii, which may 
now be called Cosoryx warrenii. It is abundant in the Santa F6 marls. 
The fracture has taken place in every instance at a point as far above the frontal 
bone as the burr of deer is situated, and is irregular in outline, higher on the one side 
than the other. In some of the specimens the smaller antlers are also broken, and ex- 
hibit a similar burr, but the terminal portion is usually lost. In one specimen, a broken 
antler is anchylosed in the usual manner of overlapping ends. The horns are solid, 
the center having a narrow, spongy axis. The surface is dense and marked by arterial 
grooves, but not pierced by noticeable foramina. 
It is evidently a question whether this genus should be referred to the hollow or solid- 
horned Ituminantia; to the Bovidce, or Cervulce. The horns might be regarded as those of 
deer were it not for the occasional specimens without burr, while the teeth are both 
cervine and bovine. We way here draw such inferences as we can respecting the 
nature of the covering of the horn. That the fractured beam should not be lost in- 
dicates the presence of some kind of covering to retain it. That this covering was not 
horny is probable from the fact that the horns are branched, a structure impossible to 
the Bovidce, since antlers effectually preveut the usual mode of increase of horn by ad- 
ditions at the base and removal at the extremity. That such covering protected arte- 
ries, which aided in the production of burrs, is also probable. We may thus believe it to 
have been dermal like that of the giraffe, or the Antilocapra, at the period of immaturity 
of its horny sheath. 
It may be concluded, then, that the genus Cosoryx represents the ancestral type of the 
Cervidce, and explains the origin of the remarkable type of horns of that family as fol- 
lows : Ruminants with fixed horns of structure more dense and brittle than others of 
the same type, in their annual combats at the rutting-season, very frequently broke 
the beams off not far above the base. The usual location of nutrition followed, which, 
being annually repeated, became as periodical in its return as the activity of nutrition 
of the reproductive system. This activity ceasing, the horn, being dense, lost its 
vitality, the more so as the normal covering would have already pqrislied in its distal 
portions. The natural consequence, the separation of the dead from the living bone 
by suppuration, would follow. This process would, however, probably require a longer 
time for tbe establishment of its periodical return than the fracture and attachment of 
the existing horn. 
This appears to be the only explanation of the origin of the phenomena exhibited 
by the horns of the Cervidce, and is suggested by the specimens of Cosoryx to be de- 
scribed. 17 
Char, specif.—This species is larger thau the C. furcatus, Leidy, and differs from the 
C. warrenii in possessing two antlers instead of one, of which the first is given off at 
a point much Farther from the base than in that species. 
The beam near the base is curved a little inward, and is semicircular in section, the 
outer face being slightly concave, the inner very convex. The base is situated a short 
distance within the free superciliary border. The beam becomes more cylindric, and then, 
expanding in a fore and aft direction, gives off an antler at right angles nearly parallel 
to the cranial axis. At a distance little over half the elevation of the first antler, the 
beam gives oft’ a second in a plane tranverse to the axis of the skull. The terminal 
portion of the beam is cylindric, curved, and acute at the apex. 
Mandibles, with teeth of two species of this genus, were found, the smaller of which 
occurring with the other portions of C. furcatus, belong to it. The larger differs in the 
elevation of the intercrescentic column of the first molar, which is worn into a loop at 
ordinary maturity ; this may, however, be but an individual variation. The diastema 
is long and the ramus of that point quite slender. 
Measurements. 
M. 
Long diameter of base, No. 1 016 
Long diameter of base, No. 2 020 
Elevation of first antler from base, No. 1 . 080 
Elevation of second antler from first, No. 3 042 
Length of terminal part of beam, No. 4 095 
Length of molars 2-5, No. 5 037 
Length of molars 4-5, No. 5 022 
Length of fifth molar 012 
Width of fifth molar 006 
COSORYX TERES, 8p. UOV. 
Established on the connected frontal bones, supporting the horns of one specimen, 
and represented by portions of horns of two others. The former individual is larger 
than any one belonging to the other species, and the species is doubtless the largest of 
the genus. The horns stand above the posterior part of the orbit, which excavates its 
base, and presenting a considerable face, descending into the temporal or zygomatic 
fossa. There is no free superciliary rini outside of the base as in C. ramosus, Cope. 
The section of the beam near the base is a regular oval; the long axis directed longi- 
tudinally and a little outward in front. The beam is erect, with a slight curvature 
outward at the inner base only. So far as preserved, it does not branch, but may do 
so in its distal portion, which is lost. The tissue is more spongy interiorly than in 
the other species; supraorbital foramen far within the superciliary border. 
M. 
Outer width between bases of horn-cores 112 
Inner width between bases of horn-cores 055 
Width of temporal fossa behind horns 053 
Long diameter of horn-core 028 
Short diameter of horn-core .021 
Length of q»art preserved 033 
This species was as large as the Antilocapra americana of the plains. 
Hksperomys loxodon, sp. nov. 
An entire mandibular ramus, with all the teeth preserved, was found in the same 
deposits as the preceding species. Molars subequal, short-crowned ; triturating sur- 
face sigmoid. The apices of the sigma on the inner side tubercular, and anterior to 
the outer apices. First molar with an additional transverse crest in front. Incisor 
compressed; outer angle of enamel face rounded smooth. Molar series oblique, rising 
anteriorly. 
Measurements. 
Measurements. 
M. 
Length of molar series 0050 
Length of first molar 0018 
Depth below last molar, (inner side) 0030 
Depth below first molar 0045 
Depth of ineisor 0015 
Depth at diastema 0027 
Panolax sanctjEfidki, gen. et sp. nov. 
Char. gen.—Molars prismatic, transverse, except the first and last; each divided by a 
plate of enamel extending transversely from the inner side. Anterior molar longitu- 
dinal ; posterior molar composed of two columns. 18 
This genus is represented by numerous teeth and portions of the cranium. It evi- 
dently belonged to the Leporidee, and is allowed to both Lepus and Palceolagus. As the 
teeth are mostly separate, it is not easy to determine which is the posterior and which 
the anterior molar. Judging by the analogy of the known species, the determination 
as here made is correct; should the relations be reversed, the species will be referred 
to Palceolagus. 
Char, specif.—The teeth are curved, the convexity inward. Inner face grooved, the 
groove occupied by cementum, the outer border compressed either without or with 
very shallow groove. First molar with triturating surface twice as long as wide, with 
an entering loop of enamel on the inner side anteriorly narrower. Last molar as wide 
antero-posteriorly as transversely, the shaft curved backward, the posterior column 
sub-cylindric half the diameter of the anterior. 
Measurements. 
Inch. 
Diameter of middle molar 
( antero-posterior 093 
transverse 187 
Diameter of first molar 
> antero-posterior 140 
> transverse 062 
Diameter of last molar 
Length of crown of last molar 250 
This species is about the size of the northern hare. 
i antero-posterior 100 
| transverse 065 
Cathartes umbrosus, sp. nov. 
Represented by numerous portions of nearly all parts of the skeleton, in excellent 
preservation. The beak from the frontal bone to near the apex is preserved ; it dis- 
plays the depression just anterior to the nares, which marks the anterior boundary of 
the cere. The culmen is nearly horizontal to just beyond this mark, and then exhibits 
a gradual decurvature to the apex. The beak is strongly compressed, and the tomia 
strongly decurved, forming an open festoon, whose middle point marks one-fourtli the 
length of the beak from the nares. The latter are directed obliquely downward and 
forward, narrowing anteriorly and having a prominent inferior bounding ledge. 
The mandible is weak, the symphisis-marking on half the length of the beak from 
the anterior angle of the nares. 
The bones of the anterior extremities exhibit large and powerful proportions, as 
compared with the posterior, appropriately to capacity for sustained fiigbt. The head 
of the humerus is much compressed, and the articular face is nearly divided into two 
by the deep bicipital groove. The head of the femur is small, and the rotular face a 
wide and deep groove. 
The tibia is slender, the shaft much compressed, with a prominent ridge. The 
cnemial crest is short, and not produced downward on the shaft. The distal posterior 
bridge is narrow and oblique. The tarso-metatarsus has a strong exterior crest, which 
constitutes half the width of the shaft. 
Inch. 
Length of beak from base of culmen, (axial) 1.90 
Length of beak from cere to apex, (axial) 1.20 
Depth of beak at culmen 87 
Depth of premaxillary at festoon 75 
Length of symphysis 69 
Length of nares 37 
Width of palate at festoon 50 
Width of head of humerus 1.37 
Width of condyles 1.13 
Width of distal end of femur i 94 
Width of head of tibia 81 
Width of condyles of tibia 66 
Width of condyles of tarso-metatarsus 75 
Length of a first phalanx 1.12 
Length of seven sacral vertebrae 1.87 
Length of two dorsal vertebrae 1.12 
Depth of a dorsal vertebra, (total) 93 
Depth of a dorsal vertebra to roof of arch 44 
Depth of centrum of roof of arch 25 
Width of centrum of roof of arch 32 
Length of two cervical vertebrae 1.12 
Depth of two cervical vertebrae to apex of neural spine 44 
Depth of articular face of centrum 17 
Width of articular face of centrum 25 
Measurements.