GECMYIDiE— THOMOMYS TALPOIDE3. 023 



sooty-blackish there. The Pacific Coast race is a rich dark-brown animal, 

 muddy-bellied, with dusky tail and feet, wholly or in part, and sooty about 

 the mouth. The Southern Interior race is usually a rich tawny or fulvous 

 animal, with partly dark tail or feet, or both, sooty mouth-parts, and white 

 pouches. This race is particularly variable in color; and, in every respect of 

 color, all the races show much variation, and, moreover, intergrade completely. 

 The various forms under which the genus Thomomys is exhibited may 

 be discriminated by the following characters: — 



ANALYSIS OF SPECIES AND VARIETIES. 



A. Large. Hind foot an inch or more long. Tail at least one-third as long as head 



and body. Above brown, reddish, &c. Below gray, brown, reddish, &c. (not 



white). Ears in a blackish area well developed 1. talpoides. 



a. Six to eight inches long; fore claws highly developed (0.45 to 0.55 long), making 



the hand about as long as the foot. Color of the house- rat, with white tail and 

 feet, and usually white about the mouth and throat ; no contrasts of dark color 

 about the mouth. (Northern Interior) a. talpoides. 



b. Seven to nine inches long; fore claws less developed, usually under 0.50, leaving 



the hand shorter than the foot. Reddish-brown, the belly muddy-brownish, 

 feet and tail usually not entirely white ; mouth-parts dark, contrasting with 

 white of the pouch-lining. (Pacific Coast) b. buJbivorus. 



c. Smaller on an average ; usually six to seven inches long. Fore claws about 0.40 



or less, leaving the hand decidedly shorter than the foot. Rich fulvous, or even 

 fawn-color, the same below but paler, variously obscured on the back with 

 dusky ; tail and feet usually dark ; face and mouth-parts sooty-blackish, sharply 

 contrasting with white pouch-lining. (Southern Interior and Lower Cali- 

 fornia) - c. umbrinus. 



B. Small ; decidedly less than six inches long. Hind foot about 0.75 ; fore foot still 



less. Tail scarcely one-fourth as long as the head and body. Above, pallid 

 yellowish-gray, with a shade of light brosvu ; below, entirely white ; feet and 

 tail white. Ears minute, not in a blackish area. Nose blackish. (Bridger's 

 Pass, Rocky Mountains) 2. clusius. 



THOMOMYS TALPOIDES, (Rich.) Baird * 



Northern Pocket Gopher 



Cricetue talpoides, Ricn., Zool. Jonrn. iii, No. 12, Jau.-Apr. 1828, 518. (Plumbago-colored.) 

 Geomys talpoides, Rich., F. B.-A. i, 1829, 204 ; Rep. Brit. Assoc, for 1836, vi, 1837, 150, 15G. tSarne as the pre- 

 ceding, but " Florida" assigned wrongly as a locality.) — DeKay, N. Y. Fn. 1842, 92. (Com- 

 piled from Richardson.) — Schinz, Synop. Mamm. ii, 1845, 137. (Compiled from Rich- 

 ardson.) — LeContk, Proc. Acad. Nat. Sci. Phila. vi, 1852, 162. (Compiled from Richardson.) 

 Saccophorus taljjoides, Fiscn., Synop. Mamm. 1829, 588 (marked " 388 "). (Compiled from Richardson.) 

 Ascomys talpoides, Wagn., Suppl. Schreb. iii, 1843, 390. (Compiled from Richardson.) 

 I'scudostoma talpoides, Aud. &, Bach., Q.N. A. iii, 1853, 43, pi. 110. (Compiled from Richardson; figuro 



from the type-specimen,) 

 Geomys (Thomomys) lalpoides, Giebkl, Siing. 1855, 530. (Compiled from Richardson.) 

 Thomomys talpoides, Baiud, M. N. A. 1857, 403. (Compiled from Richardson.)— Codes, Proc. Phila. Acad. 

 1875, 135. — Coues, Powell's Rep. Colorado R. 1875, 250 (monographic; Richardson's species 

 identified, described, aud discussed). 



"Special paper: "Short characters of a few Quadrupeds procured on Capt. Franklin's late Expe- 

 dition." < The Zoological Journal, iii, No. 12, Jan.-Apr. 1828, pp. 516-520. 



