254 



NORTH AMERICAN FAUNA 



[No. 55 



FIGURE 57. Range of five forms of pocket gophers in 

 Oregon: 1, Thomomys douglasii douglasii; 2, T. d. 

 oregonus; 3, T. niger; 4, T. quadratus quadratus ; 

 5, T. columbianus. Type localities circled. 



ETHOMOMYS DOUGLASII DOUGLASII (RICHARDSON) 



DOUGLAS'S POCKET GOPHER 

 Geomys doufflasii Richardson, Fauna Boreali-Amer., v. 1, p. 200, 1829. 



Type. Collected " near the mouth of the Columbia " at Fort Vancouver, 

 Wash., by David Douglas, probably in 1825. 



General characters. Size medium, claws rather heavy, ears medium with 

 rounded tips, skull long and narrow with flat top and abruptly decurved 

 incisors minutely grooved along inner margins ; interparietal small ; pterygoids 



U-shaped. Upper parts uni- 

 form dull hazel, slightly paler 

 on sides; lower parts lighter, 

 more ochraceous, with usually 

 a white spot on breast; nose 

 gray; feet and tail soiled 

 whitish; usually no black 

 ear patch. 



Measurements. Average of 

 typical males: Total length, 

 215 mm; tail, 64; foot, 30. 

 Average of females : 200 ; 58 ; 

 28.6. 



Distribution and habi- 

 tat. Previously known 

 only from the vicinity of 

 Vancouver, this old spe- 

 cies has been recently 

 added to the Oregon list 

 by A. W. Moore, who in 

 1926 and 1927 collected a series of specimens at Scapoose, on the 

 Oregon side of the Columbia River, some 20 miles northwest of 

 Portland (fig. 57). These specimens are almost typical and certainly 

 nearer to douglasii than to oregonus. 



THOMOMYS DOUGLASII OREGONUS MEREIAM 

 OREGON POCKET GOPHER 



Thomomys doufflasU oregonus Merriam, Biol. Soc. Wash. Proc. 14: 115, July 

 19, 1901. 



Type. Taken at Ely, near Oregon City, Oreg., by Clark P. Streator, October 

 24, 1893. 



General characters. Size medium, not half as large as bulbivorus ; ears short 

 and rounded ; incisors abruptly decurved ; fur long and soft in winter, short 

 and harsh in summer ; yellowish or bright hazel with dusky nose and cheeks 

 and black ear patch ; lower parts more ochraceous ; feet and tail soiled whitish 

 or gray. 



Measurements. Average of typical adult males : Total length, 216 mm ; tail, 

 67; foot, 29.5; ear (dry), 5. Females smaller. Weight 4 to 5 ounces (A. W. 

 Moore). 



Distribution and habitat. For many years these little yellow 

 pocket gophers were known only from the type locality, near Oregon 

 City, where a good series of specimens were taken by Streator, in 

 1893 ; but in 1921, Ira N. Gabrielson sent for identification specimens 

 collected near Canby and Sherwood and later others were taken by 

 A. W. Moore near Hillsbpro, Forest Grove, Falls City, Pedee, and 

 Summit (fig. 57). A series of specimens taken by G. G. Cantwell 

 2 miles west of Parkdale, Hood County, are not typical, but are best 

 referred to oregonus. 



