ZOOLOGY. 



ARVICOLA. 



Three specimens of arvicola were caught at Camp 94, New Year Spring. Here was a luxu 

 riant growth of gramma grass (Boutelorea) both in the valley and on the hill sides. On the 

 latter places were many loose fragments of volcanic rocks, of various sizes, scattered about, but 

 not in such quantities as to interfere materially with the growth of the grass. Here they built 

 their nests under the stones, and constructed them of dry grass in a manner similar to those of 

 the eastern meadow mouse, (Arvicola riparius,) and like this animal had paths under the 

 grass diverging in every direction from the hole. In general appearance they resembled the 

 above mentioned species, but were decidedly smaller. The specimens were all lost on the 

 Isthmus. 



ERETHIZON EPIXANTHUS, Brandt .Yellow-haired Porcupine. 



Eiethizon epixanthus, BRANDT, Mem. Acad. St. Petersburgh, 1835, 389, 416; tab. i, Animal; tab. ix, fig. 1 4, 



skull. IB. Mamm. exot. 55, (same as preceding.) 

 WATERHOUSE, N. H. Mamm. II, 1848, 442. 

 BAIRD, Gen. Rep. Mammals, 1857, 569. 



g p . C H . General color dark brown, nearly black : the long hairs of the body tipped with greenish yellow. Nasal bones nearly 

 one-half or two-fifths the length of upper surface of the skull. 



We found this singular animal only on the Little Colorado river. Our marches along that 

 stream were made during the month of December. At that season we found it frequently 

 feeding upon the tender branches of the cottonwood trees. We observed it in no other position. 

 When approached it drew itself into a bunch and remained quietly and without moving as 

 long as we remained near. The hollows in the large cottonwood trees along the stream afforded 

 them good breeding places. 



LEPUS CALLOTIS, W a g 1 e r. Jackass Rabbit ; Texas Hare. 



Le,pus callutis, WAGLER, Nat. Syet. Amph 1830, 25. IB. Lis, 1831, 51 1 . 

 Aun &, BACH. N. Am Quad. II, 1851, 95; pi. Ixiii. 

 BAIRD, Gen. Rep. Mammals, 1857, 591). 



SP. CH. Rather smaller than the European hare. Ears very long and broad; nearly one-third longer than the head and 

 one-fifth longer than the hind foot. Hair on the buttocks short and close Color above, yellowish gray, blotched and lined with 

 black. Upper surface of tail and central line of lump, black; tail beneath, grayish white Sides of rump, clear ash gray 

 Legs, ashy. Nape, black, (sometimes whitish?) Beneath, dull whitish, with a yellowish brown color on the throat. A light 

 riug round the eye. Tip of the posterior surface of the ear black. 



A specimen of this species was obtained at Fort Clark, New Mexico. Its ears are longer 

 than those of any other L. callotls I have seen, and it may belong to L. texianus, although the 

 condition of the skin is not sufficiently perfect to decide the question. 



LEFUS ARTEMISIA, B ach. Sage Rabbit. 



BAIRD, Gen. Rep. Mammals, 1857, 602. 



Several specimens of this species were obtained on the plains of Texas ; one (No. 6) in the 

 Sierra Madre, New Mexico, and another (108) at Camp 99, Picacho mountains, New Mexico. 



