100 



NORTH AMERICAN FAUNA. 



[NO. 39, 



THOMOMYS TALPOIDES CLUSIUS Coues. 

 CouES Pocket Gopher. 



(PI. II, fig. 6; PI. VII, fig. 5; text fig. 3.) 



Geomys borealis Bachman,'^ Journ. Acad. Nat. Sci. Phila. VIII, pt. 1, 103, 1839. 



Type locality said to be the "Columbia River," probably in Colorado near the 



southeast corner of Wyoming. (Not of Richardson.) 

 Pseudostoma borealis Audubon & Bachman, Quad. N. Am., Ill, 198, pi. 142, 1853. 



(Not Geomys borealis of Richardson.) 

 Thomomys clusius Coues^ Proc. Acad. Nat. Sci. Philadelphia, 1875, 138, June 15, 1875. 



Type. — Collected at Bridgers Pass, Carbon County, Wyoming, (18 

 miles southwest of Rawlins), by Dr. W. A. Hammond, July 28, 1857. 

 Type specimen in U. S. Nat. Mus. 



Distribution. — Central and soutbeastem Wyoming (north to Park- 

 man, Sheridan County), and eastern Colorado south to Colorado 

 Springs (fig. 10). 



Characters. — Considerably smaller than talpoides, with slenderer 

 claws; color slightly more rufescent; skull with the same shallow 

 rostrum, -but differing in having smaller size, large rounded bullae, and 

 lighter dentition; mammae in 6 or 7 pahs, inguinal 2-2, abdominal 

 2-2, pectoral 2-2, or sometimes 3-3; embryos 5 to 7. 



Color. — Summer pelage: Upperparts light buffy- or hazel-gray, 

 brightest on crown, paler along sides; cheeks clear gray; ear patch 

 blackish; underparts whitish or buffy; chin sometimes white; feet 

 and tip of tail whitish. Autumn pelage (September): Upperparts 

 duller and darker; crown and back dull hazel darkened with black- 

 tipped hairs that apparently fade or wear off and leave a grayish or 

 buffy brown in winter; black ear patch conspicuous. Young paler, 

 more buffy gray. 



SJcull. — Light and slender, not angular or heavily ridged; temporal 

 ridges parallel in fully adult specimens; audital bullae much larger 



1 Bachman's description of Geomys borealis, which he credits to Richardson, was based mainly on a 

 specimen collected by Townsend, of which he says, "Mr. Townsend's specimens were procured on the 

 Columbia River." The very full description of borealis, including measurements, agrees perfectly with 

 one (No. 146) of the three specimens brought back by Townsend and now before me through the kindness 

 of Dr. Witmer Stone, of the Academy of Natural Sciences of Philadelphia. I have had the skulls removed 

 from these three mounted specimens, and for the fu-st time it is possible to identify them. The old labels 

 which were formerly tacked on the stands are now attached to these specimens, and Dr. Stone thinks 

 they are in the handwriting of Le Conte, who published on them in 1852, 18 years after they were collected. 

 (LeConte also described a Geomys bursarius as Geomys oregonensis from a specimen labeled "Columbia 

 River, J. K. Townsend.") It is probable that the specimens came into the collection without labels, and 

 were supposed to have come from the Columbia River, but none of the three of T'/i07«omj/s were collected 

 anywhere near the Columbia. No. 147 is Bachman's type of townsendi and No. 144 is an adult specimen 

 of pygmaeus which Bachman considered a young of borealis. Bachman's type of borealis proves to be 

 identical with clusius of Coues. Townsend in his Narrative (p. 59) mentions a pocket gopher which he 

 picked up near Scott's Bluff, Nebr., at a point near the southeastern corner of what is now Wyoming. As 

 this specimen was preserved and is the only specimen mentioned in the narrative, it may well be the type 

 of Bachman's borealis. As Richardson two years earlier applied the name borealis to another species (tal- 

 poides), Bachman's name has no standing in this connection. The fact that Richardson had identified 

 this specimen as his borealis, and on it had drawn up a full description which was used by Bachman, does 

 not make available the name which was already a synonym of talpoides. 



