EUTÆNIA SIRTALIS PARIETALIS. (Say) Cope.

Parietal Garter Snake.

Coluber parietalis, SAY, Long's Exp. R. Mts. i, 1823, 186.—HARL. Journ. Phila. Acad. v. 1827, 349.

Eutainia parietalis, BD. & GIR. Cat. N. A. Rep. 1853, 28.

Eutania sirtalis subsp. parietalis, COPE, Check List N. A. Bat. and Rep. 1875, 41.

DESCRIPTION (No. 1180, Chief Mountain Lake). This is one of the larger species of the genus, frequently attaining a length of three feet, although, at the same time, the average dimension is less than this. It belongs strictly to the sirtalis group, and in fact is not specifically separable from that species. It is a rather slender and elegant snake; and, when found inhabiting the clear cold mountain streams or lakes, one of the most beautifully colored representatives of the genus, the stripes being firm and bold, and the dark body-color being relieved with rich red in marked contrast. The coloration as observed in life in the Rocky Mountain specimens in August is as follows:

The dorsal band, which is one scale and two half-scales broad, firm and perfectly continuous from head to end of tail, without indentation for the dark body-color, is pure yellow, fading to pale naples-yellow in alcohol. The tint is clearer than that of the lateral bands, which are ratber of a heavier golden-yellow from some suffusion with the red that beautifully mottles the sides. The lateral stripe is as firm and continuous as the dorsal one, and broader, occupying two whole scales (of the second and third rows). The body-color is black, without obvious shade of brown or olivaceous, speckled between the scales with rich vermilionred, which is very conspicuous on stretching the skin, forming an incomplete zigzag annulation. This red does not reach as high as the dorsal stripe, but extends through the lateral stripe, and occurs on the first dorsal row as a speck on the lower corner of each scale, and on the corresponding angle of the gastrosteges. The color is chiefly on the skin itself between the scales, but also suffuses the edges of many scales themselves. The first dorsal row of scales, which are much wider than the others, are colored like the belly; this lighter inferior boundary of the lateral stripe causes the stripe itself to appear less firm in outline below than above. The belly is not blackish or even slaty, but of a peculiar pale glaucous greenish, much as in sirtalis; but black appears as a pair of small, round, lateral spots on each scute at its front border. The head is olivaceous-blackish, the rostral, lorals, and labials being like the belly. Length 31 inches; tail about of the total lengthof the length of body alone. Gastrosteges 157; urosteges 64, all bifid. Superior labials seven on both sides; the fifth largest in this and a second specimen examined. In No. 1180, the labials of the left side

have a small intercalated scale between the second and third. No. 1193, from the Saint Mary's River, August, is larger than the other, measur ing about thirty-six inches; it is similar in general coloration, but less richly marked, the red suffusion being of less extent and intensity.

This slender and elegant species was only observed at and near the end of the Line, at the eastern base of the Rocky Mountains, in August. It was common in the clear cold waters of the lakes and streams, and appeared to be one of the most thoroughly aquatic species of the genus, being often seen swimming freely in deep water at some distance from the shore. At this season, all the female individuals observed were gravid with nearly matured embryos. Like other of the genus, the species is ovo-viviparous, the young being some six inches in length when born. Newly-born individuals are of an indefinite dark color, with pale bands and under parts, without red, but with two rows on each side of very evident blackish specks-markings like those that persist in the adults of E. vagrans, for example. In two young specimens found in utero, the genital or intromittent organs are external to the anus, and extremely large when compared with the size of the individual. The placental cord is attached a short distance in advance of the anus.

EUTÆNIA RADIX. (B. & G.)

Racine Garter Snake.

Eutainia radix, BD. & GIR. Cat. N. Am. Reptiles, 1853, 34 (Racine, Wisconsin).—KENN. apud Coop. & SUCKL. N. H. Wash. Terr. 1860, 299 (Minnesota).

Eutania radix, COPE, Check List N. A. Bat. and Rep. 1875, 40.

Eutania haydeni, KENN. apud COOP. & SUCKL. Nat. Hist. Wash. Terr. 1860, 298, pl. 14 (Fort Pierre, Dakota).

Thamnophis haydeni, COPE.—HAYD. Trans. Amer. Assoc. xii. 1862, 177.

DESCRIPTION (No. 1027, Pembina, June 5, 1873).-This is one of the stoutest species of the genus. A specimen two feet long equals or rather exceeds in calibre a three feet long individual of sirtalis for example. The rapidly tapering tail, in a specimen 30 inches long, is 6 inches, or contained about 4 times in the total length-nearly 4 times in the length of body alone. The head is very short and thick, with a broad obtuse muzzle. The dorsal stripe, one scale and two half-scales broad throughout, is firm and continuous along the body, but less evident (sometimes extinguished altogether) on the tail. The lateral stripe is fairly two scales wide along most of the body, but only a scale and a half posteriorly, and but one scale on most of the tail; on the body it occupies the third and, for the most part, the fourth row of dorsal scales; on the tail it descends at ouce to the first row. Both dorsals and lat eral bands are alike clear pale yellow, the former only occasionally deepening anteriorly into a more golden- or chrome-yellow. The body is olivaceous-blackish or obscure brownish-black, and of much the same tint above and below the lateral stripes. In the darkest and most "pitchy" black individuals, no markings are evident; in some lighter ones, there

are indications of obscure dark spots, scarcely or not, however, traceable in definite rows. In all the specimens, the series of spots below the lateral line are well marked and distinguishable, and in many cases the line of spots just above the lateral line is fairly perceptible. The belly is pale glaucous-olivaceous, touched with blackish ou the sides of the scutes, and sometimes this color mingles with the dark of the sides below the lateral stripe. Unlike those species in which the lateral band is lower down, there is not so much difference in the size or shape of the first and second dorsal rows. The superior labials are normally seven, sometimes eight on one or both sides; they are light-colored, like the belly, but each has a touch of blackish along the posterior border. The dorsal rows are normally 21, and all quite broad. All the dorsal scales are strongly carinated, giving the animal a roughened, scabrous appearance. The length is oftener 2 to 23 feet than more, but at all ages the bulk of the snake, as already indicated, is considerable.

The specimen here described, a gravid female, and others of the numerous ones collected, agree perfectly with the original diagnosis of the type from Racine, Wis. (whence the name "radix" is derived), and equally well with Mr. Kennicott's subsequent description of a specimen from Fort Snelling, Minn. Throughout the Red River region, from Pembina to where the Coteau de Missouri crosses the line, it is the characteristic Ophidian, the principal and almost the ouly representative of its order, outnumbering all the others put together. Indistinguishable specimens also occur in the eastern portions of the Missouri region at the same latitude, though there the greater number are of the twiningi type, which farther westward prevails altogether.

In the more fertile portions of the Red River Valley itself, this snake may be found almost anywhere in the brush and herbage. Out on the dryer prairie beyond, it is chiefly confined to the pools and streams, or their immediate vicinity. Numbers, are found basking together on the muddy borders of the sloughs, or among masses of aquatic vegetation, where they find ample subsistence during the summer months in the tadpoles, young frogs, and various water insects. They are themselves preyed upon by hawks, especially the Marsh Harrier (Circus cyaneus hudsonius) and Swainson's Buzzard (Buteo swainsoni). They are less active than some of the slenderer species, are readily caught, and when captured make little or no resistance. Only the largest individuals assume for the moment a defensive attitude and attempt to bite; most may be at once handled with impunity. The greater part of the females observed in July and August will be found pregnant, the young uumbering sometimes as many as thirty or forty. Individuals were taken in coitu in September and part of October. These observations together indicate a period of gestation protracted for the greater part of a year. The snakes become much less numerous in the latter part of September, but Dr. Coues occasionally saw them abroad on warm days up to the middle of October, even after there had been snow, sleet, and freezing of the more shallow waters.

EUTENIA RADIX TWININGI. Coues & Yarrow.

Twining's Garter Snake.

DESCRIPTION (No. 1135, Two Forks of Milk River, July 15, 1874).— From the Coteau de Missouri westward, in the arid region of the Upper Missouri and Milk Rivers, the characters of E. radix undergo considerable modification. The difference is easily recognized in life by an observer familiar with both kinds. The principal character is seen in the increased breadth and intensity of coloration of the dorsal band, especially on the anterior portion. This band is of a rich chrome-yellow or reddish-golden, contrasting strongly with the clear pale yellow of the lateral stripe. This richly-colored cadmium-yellow band commences as a minute linear trace on the middle borders of the two scales just posterior to the occipitals; it then covers a single scale in rear of these, gradually increasing until three or even four scales are covered, finally settling down to thin scales which continue down two-thirds of body, then covers one whole and two halves; opposite the anus, and to its termination, it is confined to two half-scales. At its broadest part, near the head, it is full three scales broad, and sometimes even three and two half-scales in width. There are slight or no indications of darker mottling, even in the lighter-colored specimens. Below the lateral band, the dark color is usually much broken up with mottling of the color of the belly. With much the same general form as in E. radix, the head appears decidedly narrower and less obtuse. In the specimen 1135 there are eight upper labials on right side, seven on left; it is a gravid female.

This form corresponds perfectly with certain geographical faunal areas which are represented in the region uuder consideration, a fact in further evidence of the propriety of distinguishing it. It is abundant about the prairie pools of the Upper Missouri and Milk Rivers; its habits are the same as those of E. radix. It does not appear to extend into the Saskatchewan watershed.

Dedicated to Maj. W. J. Twining, United States Engineers, in recognition of his cordial coöperation in the scientific interests of the Boundary Commission, and in expression of our personal consideration.

To the foregoing species of Ophidians observed by the Boundary Commission may be added short notices of the following, known to occur in the Yellowstone region, and very probably extending farther north:

EUTÆNIA PROXIMA. (Say) B. & G.

Say's Garter Snake.

Coluber proximus, SAY, Long's Exped. R. Mts. i. 1823, 187.-HARL. Journ. Acad. Nat. Sci. Phila. v. 1827, 353.

Tropidonotus proximus, HALLOW. Sitgreaves's Rep. Expl. Zuñi and Colorado R. 1853, 134,

146.

Eutainia proxima, BD. & GIR. Cat. N. A. Reptiles, 1853, 25.-ALLEN, Proc. Bost. Soc. N. H. xvii. 1874, 69 (Yellowstone).-KENN. apud BD. U. S. Mex. B. Surv. ii. pt. ii. 1859, Reptiles, 16.

Eutania proxima, COPE, Check List N. A. Bat. and Rep. 1875, 40.

This is a stout species, like E. radix and E. twiningi, the total length only about 3 times that of the tail. The dorsal stripe is ochraceousyellow; the lateral greenish-white or yellow on the third and fourth rows of scales; the dorsal rows are 19 in number. Carinæ of scales of dorsal region are of a whitish hue, which gives the species a streaked appearance, and the upper anterior border of the last row of scales is lined with white. There are also irregular white spots near the row of black ones above lateral line; these are more profuse in some places than others. The belly is greenish-white, more yellowish anteriorly. Its known range is east of the Rocky Mountains, from the region of the Yellowstone to New Mexico and Texas. Specimens are in the National Museum from Texas, California, Wisconsin, North Carolina, Mexico, &c. A specimen from Tomales Bay, California, is the type of E. imperialis.

EUTÆNIA SIRTALIS PICKERINGI. (B. & G.)

Pickering's Garter Snake.

a. SIRTALIS.

Coluber sirtalis, LINN. Syst. Nat. i. ed. 12, 1766, 383.-GM. Syst. Nat. i. pt. iii. ed. 13, 1788, 1107.-HARL. Journ. Acad. Nat. Sci. Phila. v. 1827, 352.-HARL. Med. and

Phys. Res. 116.-STORER, Rep. Reptiles Massach. 1839, 221.

Tropidonotus sirtalis, HOLBR. N. Am. Herpet. iii. 1842, 41, pl. 11.

Eutainia sirtalis, BD. & GIR. Cat. N. A. Rept. 1853, 30.