1 2 ZOOLOGY. 



Sp Ch. — Sizeoflbe cat squirrel, 5. cinereui. Ears large, prominent Tail mora than two-thirds as long bb the body. Abore, 

 mixi'd black, vellowiKh brown, and hniwn in indistinct inotllinRs; beneath, pale yellowish brown. Sides of bead and neck, himry 

 yelU>\ri>h, more or lest lined with black, a more distinct stripe of the same, from behind the ears on each side, extending above 

 the shoulders to the middle of the body. Ears black on their inner face. Dorsal space between the stripes scarcely darker 

 than the rest of the back. Length, 9 to 1 1 inches; tail, with hairs, 7 to 9. Hind feet, 2 to 3.30 inches. 



These animals are very abundant near the C.'comongo Rancho, and indeed throughout the 

 viilley of the San Gabriel river. They were always found living in communities, and in general 

 habits resembled the prairie dog_, SpermopkUus ludovicianus. Their size is about that of the 

 common gray squirrel, or a little larger. Their color is usually a rusty gray ; I have, how- 

 ever, seen some almost entirely black. The burrowing owl, Athene hypugaea, which is the 

 constant companion of the prairie dog, is also found among these animals in considerable 

 numbers. (No. 157. Lost on the Isthmus.) 



PSPERMOPHILUS HAREISII, Aud. & Bach.— Harris' Squirrel. 



Spe'mofkilus liarrisii, Aud. & Bach. N. Am. Quad, III, 1854, 267 ; pi. clir, fig. 1. 

 Bairi>', Gen Rep. Mammals, 18.')7, 313. 



Size rather less than that of Tamiaa striatus. Tail verlebrfe about half the length of the bndy. Ears short, pointed. Soles 

 hniry. Above, finely grizzled grayish, or whitish brown and black ; under parts, and a stripe on each side, (without any black 

 or dueky border,) whitish. Tail with one black and one light line, within the marginal whitish, black in the centre; uniform 

 whitish beneath. Length, 5 inches; tail, with hairs, about 3. Hind foot, 1.45. 



This beautiful and rare spermophile is found in considerable numbers at Cold Spring, near 

 the summit of the Sierra Madre. In this vicinity there were huge piles of scoriaceous rock in 

 which it lived. It was not very shy, but a specimen was procured with difficulty, owing to the 

 fact that it was almost impossible to kill the animal before it could escape into the rocks, and 

 avoid blowing it to pieces. Its food, in this locality, consisted of pinones and, acorns. We 

 again observed this animal near Camp 139, between the Colorado and Mohave rivers. Here we 

 found it on the hill-sides in the most rocky and inaccessible spots, and exceedingly shy. (No. 

 6. Lost on the Isthmus.) 



SPERMOPHILUS, ? 



This animal was found among the rocks on the hill-sides in the immediate vicinity of Bill 

 Williams' Fork, Camp 117. It was very active, and ran with great rapidity. It was some- 

 what larger than the S. iridecem lineatus ; its color a uniform rusty gray, its belly somewhat 

 ligbter. Its hair was rather coarse ;, its tail short and bushy. Two specimens were obtained, 

 (119,) but lost on the Isthmus, which prevents its identification. It seemed to resemble some- 

 what the S. townsendii. 



CYNOMYS LUDOVICIANUS, Rich .—Missouri Prairie Dog. 



Arclomys ludovlrianus, Oku, Guthrie's Geog. 2d Am ed. H, 1815, 292, 302. 

 Slicrmophiliis turiotirinniis, " Les-son, Manual, 214, 6.58." 



F Ci viKR, Suppl. BulTnn, 1, Mam. 1831, 316. 



All). & Bach. N. Am. Quad. II, 1851, 319; pi. xcix. 

 Ci/nomys Iwlnvicianus, Baird, Gen. Rep. Mammals, 1S57, 331. 



Size of fox squirrel, S. vulpiniis, but heavier; ears very short, not projecting above fur. Tail thort, with the hairs, aboot 

 one-third the length of body. Claws long, very stout; the thumb of the fore feet armed with a long claw instead of a flat nail. 

 Soles with a patch (.f hair. Culor above reddish brown or cinnamon, with the tips of the hairs lighter and with scattered black 

 hairs interspert ed ; btncath brow nitli white or yellow. In winter of a more grayish cast above. Hairs on the upper pari lead 



