COUES ON GEOMYS AND THOMOMYS T. UMBRINUS. 261 
Little further discussion of the synonymy of this form is required than 
is implied in what has already been said. Professor Baird appears to have 
first satisfactorily identified the Diplostojna bulbivorum of Richardson with 
the animal subsequently described as Oryctomys bottce by Eydoux and Gervais. 
Preceding authors' use of the name had been altogether compilation. Schinz's 
name is a synonym upon its face^being a mere renaming of the same animal. 
The T. laticeps was based upon the individual peculiarities of a single speci 
men, the characters of which are more or less obscured by drying after 
immersion in alcohol. 
THOMOMYS TALPOIDES UMBRINUS, (Rich.) Coues. 
Gcomys umbrinus, RICH., F. B. A. i, 1829, 202; Rep. Brit. Assoc. for 1836, v, 1837, 157. " Cadadaguios, 
Southwestern Louisiana" more likely Texas.* WATERH., Charlesw. Mag. N. H. iii, 1839, 
596, f. 71 (skull). DEKAY, N. Y. Fn. 1842, 92. (Compiled from Richardson.) SCHENZ, 
Syn. Mamm. ii, 1845, 137. (Compiled from Richardson.) LEG., Proc. Acad. Nat. Sci. Phila. 
1852, 162. (Compiled from Richardson.) 
Ascomys umbrinus, WAGN., Suppl. Schreb. iii, 1843, 389. (Compiled.) 
Pseudostoma umbrinus, AUD. & BACH., iii, 1854, 307. (Compiled from Richardson.) 
Geomys (Thomomys) umbrinus, GIEB., Sang. 1855, 530. (Compiled from Richardson.) 
Thomomt/8 umbrinus, BAIRD, M. N. A. 1857, 399 (redescribed from numerous New Mexican specimens). 
BAIRD, U. S. Mex. B. Survey, ii, pt. ii, 1859, Mamm. p. . GERR., Cat. Bones Br. Mus. 
1862, 228. 
Geomys fulvus, WOODH., Proc. Acad. Nat. Sci. Phila. 1852, 201 (San Francisco Mountains, Arizona) ; Rep. 
Expl. Zufii and Colorado R. 1853, 51, pi. 5 (the same). 
P.teudostoma (Geomys) fulvus, AUD. & BACH., Q. N. A. iii, 1854, 300. (Copied from Woodhouse.) 
TJiomomys fulvus, BAIRD, M. N. A. 1857, 402. (Describes Woodhouse's type, and other specimens, from 
California.) BAIRD, U. S. Mex. Bound. Surv. ii, pt. ii, 1859, Mamm. p. . KENN., P. R. R. 
Rep. x, 1859, Whipple's Route, Maniin. 14, pi. 12, f. 2. COUES, Am. Nat. i, 1867, 394 
(habits). COUES, Proc. Acad. Nat. Sci. Phila. 1867, 135 (Fort Whipple, Arizona). 
DIAGNOSIS. Averaging decidedly smaller than either of the foregoing. 

Length of head and body about six inches, rarely seven. Fore feet averaging 
decidedly less than the hind feet ; longest claw oftener under than over 0.40. 
Color variable, from a nearly uniform rich fawn-color all over, or even intense 
reddish-chestnut, to various tawny-brown shades, with or without a blackish 
dorsal area. Belly merely a paler shade of the color of the upper parts, or 
much as described under bulbivorus. Occasionally quite gray, much as in 
typical talpoides. (Variety : lustrous coal-black all over.) Mouth-parts, and 
often whole face, blackish, except sometimes immediately around the lips, 
* The probability is heightened by the Spanish appearance of the name, as if a corruption of 
Ciudad dc Aguas, "City of the Waters." The locality is now unknown. "Louisiana" was formerly a 
vague term. 
