COUES ON GEOMYS AND THOMOMYS T. TALPOIDES. 251 
Geomya townsvidii, "RiCH. MSS." BACHM., Journ. Acad. Nat. Sci. Pbila. 1831), 105. ("Columbia R." 
Described as distinct from "borealis," with mucb hesitation, entirely in deference to Rich- 
ardson.) RICH., Zool. Voy. Blossom, 1839, p. 12'. DEKAY, N. Y. Fn. 1842, 92. (Compiled 
from Bachman.) SCHINZ, Synop^Mamm. ii, 1845, 137. (Compiled.) 
Ascomys townsendii, WAGN., Suppl. Schreb. iii, 1843, 391. 
" Geomys unisulcatus, GRAY, Br. Mus." GRAY, L c. 
Thomomys rufescens, MAXIM., Nov. Act. Acad. Cses.-Leop. xix, pt. i, 1839, 3S3 ; Arcb. f. Naturg. 1841, pt. ii, 
42 ; ibid. 1861, ; Verz. Siiug. N.-Am. Reise, 1862, 149, pi. 4, f. 5 (penis-bone). (In tbe last 
quotation, tbe generic name^is spelled "Tomomys.") (Missouri region.) SCIIINZ, Synop. 
Mamm. ii, 1845, 134 (exclusive of tbe synonym Oryctomys bottce, Eyd. & Gerv.). (Com 
piled from Maximilian ; California erroneously assigned as tbe locality.) BAIRD, Proc. Acad. 
Nat. Sci. Phila. vii, 1855, 335; M. N. A. 1857, 397. (Redescription of specimens from 
"Nebraska," i. c., Dakota ; Forts Pierre, Randall, and Union.) BAIRD, P. R. R. Rep. x, 1859, 
Gnuuison's and Beckwith's Routes, Manmi. p. 8, pi. 10, f. 1 (tbe same). STEVENSON, U. S. 
Geol. Surv. Terr, for 1870, 1871, 462 (Wyoming). AMES, Bull. Minn. Acad. i, 1874, 70 (cata 
logued upon presumption of its occurrence in Minnesota). ALLEN, Proc. Boat. Soc. xvij, 
1874, 43 (Yellowstone River) ; Bull. Ess. Inst. vi, 1874, 56, 61, 65 (rather supposed tban 
known to be tbis species). 
Geomys rufcsccns, LECONTE, Proc. Acad. Nat. Sci. Pbila. vi, 1852, 161. (Redescribed from types of " bore 
alis" and " townseiidii," in Philadelphia Academy, marked " Columbia River.") 
Ascomys rufe-scens, WAGN., Snppl. Scbreb. iii, 1843, 387. 
Geomys (Thomomys) rufcscens, GIEBEL, Sang. 1855, 530. 
Thomomys "fulmts", MERR., U. S. Geol. Surv. Terr, for 1872, 1873, 665. (Nee Woodb. Err. test, specim. 
ipsis.) 
DIAGNOSIS. Coloration almost exactly that of the house- rat (Mus clecu- 
manus) sometimes assuming a more reddish phase, occasionally blackish- 
plumbeous ; tail and feet white, and much of the chin, throat, and breast 
white in irregular patches, where the fur is white to the base. No sooty- 
blackish about the mouth-parts ; no obvious distinction in color between the 
pouch and its surroundings ; no strongly-pronounced reddish-brown on the 
under parts ; general tone of coloration never decidedly tawny. Ears set in 
a small blackish area. Length 6 to 8 inches ; tail 3 inches or less, decidedly 
less than half the length of head and body ; fore and hind feet (claws included) 
approximately equal to each other, about 1.25; longest fore claw little less 
than the length of the rest of the hand, about 0.50. 
HABITAT. Supposed to occur in the Interior of North America, from 
"Hudson's Bay" to the "Columbia River", and to occupy about the northern 
half of the United States west of the Mississippi, exclusive of the Pacific- 
coast region ; being replaced, to the west, by T. bulbivorus, and, to the south, 
by T. umbrinus. Undoubted specimens seen from Selkirk Settlement, British 
America ; from Minnesota westward along the parallel of 49 N. to the Rocky 
Mountains, and from Idaho, Wyoming, Utah, and Nevada. 
Description (from a series of skins taken by myself along the northern 
