In the academic year of 1947-48 Montague studied the geographicvariation in Thomomys talpoides of Wyoming. His studywas based upon materials then in the University of Kansas Museumof Natural History. Publication of the results was purposelydelayed until previously reported specimens from certain adjacentareas, especially in Colorado, could be examined. In the autumnof 1950 one of us, Hall, was able to examine the specimens fromColorado; also, the specimens from Wyoming accumulated in thepast two seasons of field work in Wyoming were examined byHall. A result of these studies is the recognition of two heretoforeunnamed subspecies of the northern pocket gopher in southeasternWyoming.
Grateful acknowledgment is made of the opportunity to study theColoradon specimens in the Biological Surveys Collection of theUnited States National Museum, and of the financial assistancefrom the Kansas University Endowment Association which permittedthe field work in Wyoming.
Descriptions and names for the two new subspecies are givenbelow:
Thomomys talpoides rostralis new subspecies
Type.—Female, adult, skull and skin, no. 17096 Mus. Nat. Hist., Univ.Kansas; from 1 mi. E Laramie, 7164 ft., Albany County, Wyoming; obtained onJuly 16, 1945, by C. Howard Westman; original no. 320.
Range.—Southern Wyoming and south in the mountains of Colorado to theArkansas River but not including the Colorado River drainage except in GrandCounty and part of Routt County.
Diagnosis.—Size medium (see measurements); upper parts ranging frombetween Cinnamon-Rufous and Hazel (capitalized terms are of Ridgway, ColorStandards and Color Nomenclature, Washington, D. C., 1912) in the easternpart of the range to between Argus Brown and Brussels Brown in the westernpart of the range; sides Cinnamon-Rufous; throat whitish; remainder of under-partswhitish, in many specimens tipped with Ochraceous-Buff; feet and tailwhitish; rostrum long; nasals ordinarily truncate posteriorly; temporal ridgesnearly parallel; interpterygoid space broadly V-shaped.[Pg 4]
Comparisons.—From Thomomys talpoides clusius (topotypes), T. t. rostralisdiffers in: Body longer; color more reddish (lighter with less brownishand more ochraceous); rostrum both longer and broader, actually and also inrelation to length of the skull; skull broader interorbitally; upper molari