AUTHOR’S EDITION. DEPARTMENT OF THE INTERIOR. UNITED STATES GEOLOGICAL AND GEOGRAPHICAL SURVEY F. V. HAYDEN, U. S. Geologist-in-Charge. FIELD HOTES ON BIRDS OBSERVED IN DAKOTA AND MONTANA ALONG THE FORTY-NINTH PARALLEL DURING THR SEASONS OF 1873 AND 1874. Dr. ELLIOTT COUE8, U. S. A., LATE SURGEON AND NATURALIST U. S. NORTHERN BOUNDARY COMMISSION, EXTRACTED FROM THE BULLETIN OF THE SURVEY. Vol. IV. No. 3. Washington, July 29, 1878. ART. XXV.—FIELD-NOTES ON BIRDS OBSERVED IN DAKOTA AND MONTANA ALONG THE FORTY-NINTH PARALLEL DURING THE SEASONS OF 1873 AND 1874.* By Dr. Elliott Coues, U. S. A., \ Late Surgeon and Naturalist U. S. Northern Boundary Comm The following notes result from observations made in the field duftriig my connection with the Uuited States Northern Boundary Commission— Archibald Campbell, Esq., Commissioner, Major W. J. Twining, Corps of Engineers, U. S. A., Chief Astronomer. The line surveyed by the Com- mission in 1873 and 3874 extended from the lied River of the North to the Rocky Mountains, a distance of 850 miles, along the northern border of the Territories of Dakota and Montana, in latitude 49° north. During the season of 1873, I took the field at Pembina, on the Red River, early in June, and in the course of the summer passed along the Line nearly to the Coteau de Missouri, returning from the Souris or Mouse River via Fort Stevenson and the Missouri to Bismarck. This season’s operations were entirely on the parallel of 49°, and in the water- shed of the Mouse aud Red Rivers, my principal collecting-grounds being Pembina, Turtle Mountain, and the Mouse River. This region, of the northerly waters is sharply distinguished geographically and topographically, as well as zoologically, from the Missouri and Milk River Basin, which I entered the following year. In 1874, I began at Fort Buford, at the mouth of the Yellowstone, travelled northwesterly to 49°, which was reached at Frenchman’s River, one of the numerous tribu- taries of Milk River, and thence along the parallel to the Rocky Mount ains at Waterton or Chief Mountain Lake and other headwaters of the Saskatchewan; returning back on the Line to Three Buttes or Sweet- grass Hills, thence direct to Fort Benton, Montana, and thence by a boat voyage down the Missouri to Bismarck. In neither season was much collecting done except along the parallel itself; and the operations of each season were in a region sharply distinguished, as I have said, by its faunal peculiarities. From these two broad belts of country, cor- responding at 49° nearly to the Territories of Dakota and Montana respectively, is to be set apart a third, that of the Rocky Mountains alone. I made an elaborate comparison of the faunal characters of these three [*For articles on other portions of the same writer’s collection, see this Bulletin, this Vol., No. 1, pp. 259-292, and No. 2, pp. 481-51©.—Ed.] 546 BULLETIN UNITED STATES GEOLOGICAE SURVEY. regions with reference to anticipated publication in connection with the official report of the United States Boundary Commission; but the present is hardly the place to present these considerations in detail. I may, however, state that my results agree closely with those derived from the geological investigations made by Mr. George M. Dawson, my colleague of the British contingent of the Survey, whose valuable Report should be consulted in this connection, and that they are in striking accord with what would be the geographer’s or the topographer’s con- sideration. 1. Red River region, or watershed of the lied and Mouse Rivers. At 40° this extends westward along the northern border of Dakota, nearly to Montana,—to the point where the Coteau crosses the Line. The bird- fauna of this region is decidedly Eastern in character,—much more so than that of the portion of the Missouri Basin which lies south of it and no further west. It is well distinguished, both by this Eastern facies and by the absence of the species which mark the Missouri region. The region consists of more or less (nearly in direct ratio as we pass westward) ler- tile prairie, treeless except along the streams, cut by the two principal river-valleys, the Red and the Mouse, crossed by the low range of the Pembina Mountains, and marked by the isolated butte known as Turtle Mountain. It is bounded to the west and south by the Coteau,—a com- paratively very slight ridge, which nevertheless absolutely separates the two great watersheds. The Red River flows nearly due north; the Mouse River makes a great horseshoe bend, at first directed toward the Missouri, which it almost reaches before it is “bluffed off”, literally,and sent northward.* The bird fauna of Pembina and the whole immediate Red River Valley is thoroughly Eastern. The only Western trace I ob- served was Spizclla pallida and some Icteridce, especially Scolecophagus cyanoccplialus; though Sturnclla neglecta and Xanthoccplialm icterocepha- lus are both common prairie birds much further east, as Pcdicecetes co- lumbianus also is. Characteristic mammals are Spermophilus 1 o-lineatus, /S'. franlclini, Tamias quadrivittatus, Thoniomys talpoides, and the rare Onychomys lencogasler. Out on the prairie, beyond the Pembina Mount- ains, this region is distinguished by the profusion cl' several very nota- ble birds,—Antlius spraguii, Plectropkanes ornalus, Passer cuius bairdi, aud Eremopldla leucolxma, all breeding, none of them observed at Pembina. Here also was found Coturniculus lecontii. This treeless area is fur- ther marked by the absence of sundry birds common enough in the heavily-timbered Red River Valley, as Empidonaces, Vireones, Antrosto■ * Fort Pembina is situated ou the Red River, latitude 49° nearly ; longitude 9?° 13, 42" west; altitude 790 feet above sea-level. The Pembina Mountains, well wooded, with a maximum elevation of about 1,700 feet, lie 35 miles west of the Red River, forming an escarpment which separates the low immediate valley of the Red River from the next higher prairie steppe, which reaches to the Cotean. Turtle Mountain is an isolated, heavily-wooded butte, 125 miles west of Pembina, with an elevation of about 2,000 feet above sea-level, lying directly on the parallel of 49°. Our camp, at its west base, was in longitude 109° 307 41.1", distant 149.25 miles from Pembina along the parallel. COUES ON BIRDS OF DAKOTA AND MONTANA. 547 m us voc ferns, Turdus pallasi, Geo Oily pis Philadelphia, Goniaphca ludovi- ciana, Sctophaga ruticilla, and many others. Spermophilus richardsoni begins in this region, aud 8. franklini and doubtless Onychomys end here. There are Badgers in plenty and a few Antelopes; there were no Buffalo in 1873, though the country was still scored with their trails, and skeletons were plenty from the Mouse River westward. This region is still more strongly marked by the absence of the Missouri specialties. 2. The Missouri region, or the great watershed of the Missouri and Milk Rivers. As soon as we cross the Coteau, the whole aspect of the country chauges, and there is a marked difference in the fauna. We enter a much more sterile and broken region, absolutely treeless except- ing along the larger water-courses, full of “ bad lands”, with much sage- brush,—such country stretching, with scarcely any modification, to the base of the Rockies. In this latitude, the Milk River is the maiu artery, with many north-south affluents crossing 49°. The characteristic mam- mals are the Buffalo (first seen in 1874 in the vicinity of Frenchman’s River), Antelope, Prairie and Sage Hares [LL. campestris and sylvaticus var. nuttalli), the Prairie “ Gophers” (Spermophilus richardsoni, in extra- ordinary abundance), and Prairie “Hogs” (Cynomys ludovicianus), some of these being perfectly distinctive of the Missouri as compared with the Red River region. Putorius longicauda is the Ermine of this region. Kit Foxes (Vulpes velox) are common, but so they are along the Mouse River. The characteristic birds are Calamospiza bicolor, Tyrannus ver- licalis, Plecfrophanes maccoicni, Pica hudsonica, ISpeotyto hypogcca, Centro- cerctis.urophasianus (diagnostic of the region, like the mammal Cynomys ludovicianus, or the reptiles Phrynosoma douglassi and Crotalus conjlucn- tus), and Eudromias montanus. Few, if any, distinctively Eastern birds extend across or even into this region. Plcctrophanes ornatus goes to the mountains, but in diminished numbers; one specimen of Neocorys was taken near the mountains, but neither Passerculus bairdi nor Cotur- niculus lecontii was observed; Eremophila continues in full force. The Svveetgrass Hills, or Three Buttes, are the most considerable out- liers of the Rocky Mountains, along the parallel of 49°, quite isolated on the prairie. I noticed no avian specialties here, but Mountain Sheep were comparatively abundant (as they were also along the bluff's of tho Missouri River, above the mouth of the Yellowstone), and the Yellow- haired Porcupine, Eretliizon cpixanihus, was numerous. 3. Roclcy Mountain region.—Rising gradually and, of course, imper- ceptibly, the Missouri region maintains its features to the very foot of the mountains, the headwaters of the Milk River being prairie streams, sluggish, warm, and muddy, with much alkaline detritus. The divide between this, watershed and that of the Saskatchewan is too slight to be recognized as such by an inexperienced eye; on passing it, wo strike the cleat, cold, turbulent stiearns from the mountains, abound- ing in tialmonidcc, and soon enter the woods. This region is strongly marked, not only by “ Western ” species, in the geographer’s sense, but 548 BULLETIN UNITED STATES GEOLOGICAL SURVEY. by Alpine forms, strangers to lower altitudes at the same latitude, by exclusively arboreal forms, and by abrupt disappearance of the prairie types mentioned in the preceding paragraph. The marks of the region, as compared with the prairie, are unmistakable. We here find Lagomys princeps (down to 4,500 feet), Tamias lateralis, Sciurus hudsonius var., Neotoma cinerea, Arctomys Jlaviventris, among mammals ; large game was scarce,—a few deer (C. virginianus), a bear or two, and an alleged Aploccros montanus. There were no live Buffalo, but plenty of skulls and skeletons far into the mountains. Among notable birds may be mentioned Cinclus mexicanus, Dendrceca audubani, Geo tidy pis maegilliv- rayi, Ampelis garrulus, doubtless breeding !, Perisoreus canadensis, Empi- donax hammondi, E. obscurus, Selasphorus rvfus, Pious liarrisi, Asyndes- mus torguatus, the two Alpine Grouse, Tetrao franklini and T. richardsoni (together with Pedicecetes, which pervades all three regions), Encephala islandica (breeding), and Eistrionicus torquatus (breeding). Some of the more conspicuous birds of the three regions, or of any one of them, may be tabulated in the following form. The implication in each case is simply my own observations, not the known general range of the species. All the species in this table, doubtless even Ampe- lis garrulus, were on their breeding-grounds, excepting a very few migrants seen early in June at Pembina. Red River region. Missouri region. a c« "3 . §i 3 3 a 1 Red River region. Missouri region a 3 a C? 0 & u o-.g M * § « x x x x X x x x x x x x X x x X x x x x x X x x x x x x x x x x X x X x x x x x 1 x X x x x ? x x x x X x x x x x x X X x x x x ? x x ? x x x 1 x x x X x x x Pica liudsouica X X Histrionic us torqualus X The list herewith is restricted to the birds actually observed and generally shot. COUES ON BIRDS OF DAKOTA AND MONTANA. 549 There remains the agreeable duty of witnessing the ready and unvary- ing courtesy extended to the Naturalist of the Commission by Mr. Camp- bell and Major Twining, who sought to aid by all means in their power the scientific interests he had in charge; and by Captain W. F. Gregory, Corps of Engineers, U. S. A., to whose party he was attached during the season of 1874. TUBDUS (PLANESTICUS) MIGBATOBIUS, Linn. The Bobin. Found in abuudance at Pembina, where it was breediug iu the wooded river bottom. In this latitude, the eggs are generally laid during tho middle and latter parts of Juue, and I scarcely think that more thau ouo brood is reared annually. Further westward the species seems to occur chiefly during the migrations, as most of the country is unsuited to its wauts. In September, large numbers were observed in the fringes of trees along the Mouse Biver. During the secoud season, the birds were again found on the Upper Missouri Biver and iu the Bocky Mountains. On the whole, the species is much less numerous, excepting in the immediate valley of the Bed Biver, thau it is iu settled and wooded portions of the United States, and probably none pass the winter iu this latitude. List of specimens. A "o O <£ CC Locality. Collector. Length. V H W tb a % Nature of specimen, and remarks. 2953 2954 2985 3117 3126 3130 3131 3756 9 Pembina, Dak do June 12,1873 do Elliott Cones. Skin. June 14,1873 June 22,1873 June 23,1873 June 24,1873 do Egg. Three eggs. Nest with 5 eggs. Nest: young in al- cohoL Skin. Mouse River, Dak .. Sept. 16,1873 . ...do ri’RDUS (I1YL0CICIILA) PALLASr, Cab. Hermit Thrush. The Hermit Thrush was not observed during the Survey until toward the clore of the second season, when specimens were taken in the Bocky Mountains near Chief Mountain Lake, under circumstances which left no doubt of its breeding in the vicinity. As it is, however, a common species of wide distribution in North America, it is doubtless to be found, like the Bobin, wherever timber grows, along the line of tho Northern Boundary. 550 BULLETIN UNITED STATES GEOLOGICAL SURVEY. List of specimens. Coll. No. M V Ifl Locality. Date. Collector. Length. Extent. fcb a k Nature of specimen, and remarks. 4531 4600 .... Rocky klonn tains, lilt itudo 49°. do Aug. 20,1874 Aug. 25,1874 Elliott Coucs. do Skin. ....do. TUKDtJS (HYLOOICULA) SWAINSONI, Gab. Olive-backed Thrush. The remarks made under head of the last species* with regard to geographical distribution, are equally applicable to the present one. It was only observed, however, in September, during the general autumnal migration, in the slight fringe of trees along the stream where I was collecting at tha time. In a country so nearly treeless as is the tract lying between the Red River and the Rocky Mountains, the slightest pieces of woodland are eagerly sought by all the migrants as stopping- places for food and rest. Though at other seasons tenanted by few species, they become populous iu the fall by the presence of great numbers of small insectivorous and granivorous species, among which the Turd'idce, Sylricolidce, and Fringillidoe are conspicuous. List of specimens. Coll. No. & Locality. Date. Collector. Length. Extent. tb p £ Nat ure of specimen and remarks. 3759 Mouse River, Dak .. Sept. 16,1873 Elliott Coues. 7.50 12.10 3.60 Skin. TURDUS (HYLOCICHLA) FUSCESCENS, Steph. Veery, or Wilson’s Tiirush. Unlike either of the preceding species, the Veerv does not appear to extend westward beyond the Valley of the Red River,—at any rate, it was only observed in the vicinity of Pembina. Here it was found breeding in abundance during the mouth of June, when its exquisite song eidivened the tangled recesses of the wooded liver-bottom, in which the timid birds secreted themselves, and formed one of the most characteristic pieces of bird-melody to be heard in that ill-favored locality. A nest was found on the 9th of June, containing four fresh eggs, uniform, blui h green in color, and measuring about 0.86 in length by 0.66 in diameter. It was placed upon a small heap of decayed leaves which had been caught ou the foot stalks of a bush a few inches from the ground, and composed of weed-stems, grasses, and fibrous bark- strips, woven together, and mixed with withered leaves. The walls were COUES ON BIRDS OF DAKOTA AND MONTANA. 551 thick, giving a bulky, irregular, and rather slovenly appearance, and causing tbe cavity to appear comparatively small,—it was only about 2£ inches in diameter by less than 2 inches in depth, though the whole uest was as large as a child’s head. List of specimens. o 'A 6 H ZJ m Locality. Date. Collector. Length. Extent. tt a £ Nature of specimen, and remarks. 2927 2055 2978 9 Pembina, Dak June 9,1873 June 12,1873 June 14,1873 Elliott Coues Skin, with nest anti Skin688' 7. 75 12.25 MIMTJS CAROLINENSIS, {Linn.) Gray. Catbird. The Catbird was ascertained to be one of the common species of the Red River region, where it was breeding in June, in situations similar to those it selects in the East. 1 traced it westward to Turtle Mountain, but did not observe it again in the Rocky Mountains, where its presence was to have been expected. It is also a rather common species on the Upper Missouri and the northern affluents of this and of the Milk River. The Missouri appears to be tbe highway by which the species gains the Rocky Mountains, as observed by Dr. Hayden. The naturalists of the Northwest Boundary Commission collected specimens in Washington Territory, and Sir John Richardson has left a record of its occurrence in the Saskatchewan region as far north as latitude 54° north. As at Pembina, the bird was breeding in June in the shrubbery along tbe Upper Missouri and its tributaries. List of specimens, Coll. No. A Locality. Date. Collector. Length. Extent. . he p £ Nature of specimen and remarks. 2958 3001 3114 3127 3217 3352 4024 4025 June 13,1873 Juno 19,1873 June 22,1873 Juno 23,1873 Elliott Coues. Nest with 4 eggs. Nest with 2 eggs. Three eggs. Two eggs. Nest with 5 eggs. Skin. Skin ; nest with 3 eggs. Skin. .... Turtle Mountain, L)ak. Big Muddy River, Mont. do J uly 23,1873 June 22,1874 ....do do HARPORHYNCHUS RUFUS, {Linn.) Cab. Thrasher, or Brown Thrush, Observed at Pembina, which appears to be near the northern limit of the distribution of this species. In other latitudes, however, it extends 552 BULLETIN UNITED STATES GEOLOGICAL SURVEY. further westward, having been found by earlier expeditions in various portions of Dakota, Nebraska, Wyoming, and Colorado. It is one of the species of Turdidce which does not appear to leave the United States in winter, as we have no West Indian or Central American quotations. It breeds in suitable localities anywhere within general range. A nest containing four eggs was found at Pembina late in June. During the second season, the species was observed on the Missouri above Port Buford. List of specimens Coll. No. • cr. Locality. Date. Collector. Length. | Extent. tt 8 £ Mat ure of specimen, and remarks. 3084 Pembina, Dak Near Fort Buford, Dak. .lune 21,1873 July —, 1874 Elliott Cones do Nest with 4 eggs. (Not preserved.) C1NCLUS MEXICAN US, Sic. American Dipper, or Water Ouzel. During the tedious march through the monotonous country of the Milk Iiiver, when little was to be looked for that had not already been found, I daily indulged pleasant anticipations of change for the better, in the new and more varied features of the avifauna which I should meet on entering the mountains. I was particularly desirous of finding the Dipper,—a bird that in former years had given me the slip when l was crossing the mountains of New Mexico and Arizona. Nor was 1 disappointed ; the most favorable conditions of the bird’s existence are met in the many crystal cascades, fed by the snow-capped peaks that form Chief Mountain Lake,—a beautiful sheet of water environed by pre- cipitous mountains, debouching with a tortuous course into one of the many clear streams that unite to form the Saskatchewan. Nor was this romantic spot the home of the Dipper alone, among the more interesting forms of animal life. The Bohemian Waxwing was breeding here, many degrees of latitude further south than had been known before. So was the Harlequin Duck, like the Waxwing then for the first time ascer- tained to rear its young within the limits of the United States. Bar- row’s Golden Eye and other species, to me, at least, extremely interest ing, were here first encountered, as more fully noted in other portions of this narrative. At the time of my visit, it was too late to look for the nest or eggs of the Dipper, as the young were already on wing; that they were bred in the immediate vicinity, at an altitude of only about 4,000 feet, was evi- dent from the immature condition of the specimens examined. My observations upon the habits of the species were too limited to enable me to add anything to the account, compiled from various sources, which was published in the “Birds of the Northwest”. COUES ON BIRDS OF DAKOTA AND MONTANA. 553 List of specimens, 6 *A -j o O X D eft Locality. Date. Collector. Length. Extent. .S £ Nature of specimen, and remarks. 4545 Rocky Mountains, latitude 49°. Aug. 21,1874 Elliott Couea. Skin. SIALIA AKCTICA, Sic, Rocky Mountain Bluebird. The Northern Boundary appears to be slightly beyond the limit of distribution of the Eastern Bluebird, since the species was not ob- served at Pembina, where the avifauna is almost entirely Eastern iu its composition. The Western Bluebird, 8. mexicana, is still further re- moved from the region now under consideration. The third and only Other species of this country has a more northerly distribution than either of the others, reaching to about latitude 01° or 65° north; it is found from the eastern foothills of the Rocky Mountains to the Pacific, and in some localities is very abundant. A few individuals were ob- served by the Commission in the Rocky Mountains, at Chief Mountain Lake, but no specimens were preserved. Its habits are much the same as those of its well-kuowu Eastern cougener. REGULUS CALENDULA, Liclit. Ruby-crowned Kinglet. This species, of general distribution throughout the wooded portions of North America, was observed on Mouse lliver, in September, during the autumnal migration, frequenting the dense undergrowth of the river-bottom in company with Helminthopliaga celata and Dendrceca coronata. In its spring and autumn movements, it undoubtedly passes the several wooded poiuts of the line, and may yet be found breeding in the mountains in this latitude. Its nest and eggs long remained among the special desiderata of American ornithologists. So far as known, no authentic specimens reached our hands until two or three years ago, when Mr. J. H. Batty, then attached to Dr. Hayden’s Survey, discovered a nest in Colorado, July 21,1873. It was placed on a spruce bough, about 15 feet from the ground, and contained live young and one egg. The structure, which I have examined at the Smithsonian, is larger than such a tiny architect would be expected to produce, and consists of a loosely blended mass of hair and feathers, mixed with moss and short pieces of straw. Other observers, notably Mr. T. M. Trippe, had previously indicated the undoubted breeding of the species iu the higher wooded portions of Colorado, which is confirmed by the discovery of this nest. 554 BULLETIN UNITED STATES GEOLOGICAL SURVEY. It is a very curious fact, in the history of this'genus, that a variety of Eegulus calendula, or a very closely allied species, should be among the few resident birds which constitute the isolated fauna of the island of Guadeloupe, 200 miles south of San Diego, Cal. PARUS ATRICAPILLUS SEPTENTRIONALIS, Harris. Long-tailed Chickadee. An abundant resident of the region of the Upper Missouri, in all suitable situations; but neither this nor any other species of the genus was noticed in the Red River Valley. It is the characteristic form of the whole Rocky Mountain region from the Fur Countries into Mexico, where it is the only representative of tho genus, excepting P. montanus. Detailed measurements of a series of specimens of this disputed form, for comparison with those of P. atricapillus, will be found in my work already quoted. These were carefully made in the flesh, at Fort Ran- dall, during the winter of 1872-73. The average length was found to be 5.50 inches; the wing, 2.40 to 2.75; and the tail, 2.G0 to 2.80. A specimen procured at Chief Mountain Lake is preserved among the collections of the Commission. List of specimens. Coll. No. | Sex. Locality. Date. Collector. Length. Extent. u a £ Na ture of spec'men, and lemarks. 4G34 .... Rocky Mountains, lat. 40°. Aug. 28,1874 Elliott Coues Skin. TROGLODYTES AEDON, ViciU. House Wren Observed as far west as the confines of the Missouri Coteau. Tho westernmost specimens, as well as those from tlie immediate valley of the Red River, appear to be typical a'edon. The Eastern form has also occasionally been met with in the Missouri region itself; though there the prevailing type is the var. parJcmanni. On the Red River, in June, the species was breeding very abundantly in the neighborhood of the fort and town of Pembina. Lint of specimens. Coll. No. •X'S Locality. Date. Collector. Length. a W fci> a £ Nature of specimen, and remarks. 2791 3104 3115 3132 3173 3727 3744 Pembina, Dak do .. do ,Tline 2,1873 June 2.’, Is73 Elliott Couoe do do do ...do 4. 90 6. 70 *••• Skin. do. Nine eggs (2 sets). Nest wit h 5eggs. Five eggs. Skin. do. June 24,1873 June 26,1873 Sept, 3,1873 Sept. 11,1873 Mouse River, Dak .. Long Coteau River, Dak. -...do do 5.00 0.75 :::::: COUES ON BIRDS OP DAKOTA AND MONTANA. 555 CISTOTHORUS STELLARIS, (Licht.) Cab. Short billed Marsh Wren. The present is one of a few species of general distribution in the East- ern Province, which appears much more abundant along its line of migration in the Mississippi Valley than on the Atlantic coast. In the East, the species does not appear to have beeD observed beyond Southern New England. The present specimens, secured at Pembina in June, and later in the season along the Mouse River, are the northernmost on record, probably representing about the limit of its distribution in this rjmirter. The species has been observed westward to the Loup Fork of the Platte. I found the birds to be rather plentiful along the Red River, in low, oozy ground overgrown with scrub willows, and also in the reedy sloughs of the prairie. They were undoubtedly breeding here, though no nests were secured. List of specimens. 6 ft c O H o 02 Locality. Date. Collector. Length. Extent. Wing. Nature of specimen, and remarks. 2910 3451 d* Pembina, Dak Mouse River, Dak .. June 4,1873 Aug. 9,1813 Elliott Coties do 4.50 5.15 Skin. TELMATODYTES PALUSTBIS, (Wih.) Cab. Long-billed Marsh Wren, This species was not observed till we reached the Rocky Mountains, when a few were seen on marshy ground near Chief Mountain Lake. It is, however, of undoubted occurrence in suitable situations along the Line. EREMOPHILA ALPESTR1S LEUCOL.EMA, Cones. Western Horned Lark. One of the most interesting points in the history of the Horned Lark is its peculiar distribution during the breeding-season. Its breeding- range is in no way related to zones of latitude, nor yet is it determined by altitude, but by the topographical features of the country. It rarely, if ever, stops to breed along the Atlantic coast so far south as New England, where the surface of the country is not adapted to its peculiar wants. It is stated to occasionally nest in portions of Canada West; but it is not until we reach the valley of the uppermost Mississippi, in a broad sense, that we find the bird regularly breeding within the United States. I am informed by Mr. W. K. Leute, who accompanied the expe- dition during the season of 1873, that it nests in Wisconsin, near Racine, laying about the middle of April, even before the snow is off the ground. 556 BULLETIN UNITED STATES GEOLOGICAL SURVEY. From the lied River and corresponding longitude, west to the Rocky Mountains, it breeds in profusion, and during the greater part of the year it is, without exception, the most abundant, universally diffused, and characteristic species of the prairie avifauna. Numerous specimens were taken, not only along the parallel of 49°, but also on the Missouri and Milk Rivers, and the species accompanied our line of march into the mountains. The individuals bred in this dry and sterile region are usually lighter-colored than those of better-watered areas, and are those which I have designated by the term leucolccma, in indication of a slight geographical differentiation. The Horned Lark is one of the few species which, in this latitude, usu- ally rear at least two broods each season,—a fact which in part accounts for the preponderance of individuals over those of the species with w hich they are associated. I have already adverted to the extremely early nesting-time which has been ascertained, and have only to add that the period of reproduction is protracted through July. I have observed young birds on the wing in June, and found fresh eggs in the nest dur- ing the latter half of July. In fact, all through the summer months the troops of Larks everywhere to be seen consist of old birds mixed with the young in all stages of growth. The great flocks, however, are not usually made up until the end of the summer, when all the young are full-grown, and the parents, having concluded the business of rear- ing their young, have changed their plumage. The young of the first brood soon lose the peculiar speckled plumage with which they are at first covered; the later ones change about the time the feathers of the old birds are being renewed. The agreeable warbling song is scarcely to be heard after June. While it is not probable that any of these birds endure the full rigors of winter in the exposed country of this latitude, I am unable to say when they retreat. They continue abundant until October, and prob- ably only retreat before the severe storms of the following month, to return again in March, if not in February. It is brave and hardy, one of the few birds that weather the terrible storms that usually prevail in April in the Missouri region. The nest of the Horned Lark may be stumbled upon anywhere on the open prairie. It is a slight affair,—merely a shallow depression in the ground, lined with a few dried grass-stems. The eggs are four or five in number, measuring nearly an inch in length by about three-fifths in breadth; they are very variable in contour. The color is well adapted to concealment in the gray-brown nest, being nearly the color of the with- ered materials upon which they rest, thickly and uniformly dotted with light brown. The eggs and young birds, like those of other small spe- cies nesting on the ground in this region, often become the prey of the foxes, badgers, and weasels, if not also of the gophers. The Horned Lark is a sociable bird, not ouly highly gregarious with its own kind, but one that mixes indiscriminately with several other spe- 557 COUES ON BIRDS OF DAKOTA AND MONTANA. cies, as Sprague’s Lark, the Savanna Sparrow, Baird’s, Maccown’s, and the Chestnut-collared Buntings, all of which are abundant birds of the same region. List of specimens. © o O Sex. Locality. Date. Collector. Length. u a £ Nature of specimen and remarks. Sept, 1-2 1873 Skin. 3855 ....do ’ Oct. 1,1873 do 7.00 13.90 4.50 ... .do. 385C do 7.40 13.75 4. 50 do. 3857 7.30 13.50 4.30 do. 4007 Porcupine R., Mont Juno 20,1874 do Skin. ha iry (young) 4150 July 7, 1874 Mont. 4151 4157 ....do. 4158 ......do’ 4159 4245 Q July 18,1874 Mont. eggs, same No.). 4246 Skin. 4247 do 4252 July 21,1874 River, Mont. 4253 4323 Sweetgrass Hills, Aug. 6,1K74 J. H. Batty... 6.50 14.75 4. 00 do. Mont. 4335 West of Sweetgrass Aug. 7,1874 Elliott Coues Hills, Mont. 4345 Aug. 8,1874 4423 •Au'r. 12, 1874 4424 do .... 4404 Aug. 15,1874 Mont 4470 4021 Rocky Mts., latitude Aug. 26,1874 J. H. Batty... 49°. 4600 West of Sweetgrass Aug. 30,1874 ....do Hills. 4667 4668 4669 4674 do .. 4682 Auer. 31.1874 4683 _ 3500 do 6. 50 10. 65 do. COUES ON BIRDS OF DAKOTA AND MONTANA. 563 List of specimens—Continued. Coll. No. M Locality. Date. Collector. Length. Extent. Wing. Nature of specimen, and remarks. 3501