40 



ITORTH AMERICAN FAUNA. 



[no. 39. 



i^. Audital bullae relatively narrower. 

 ^"^ Size larger, hind foot of ^ about 28. . . . columbianus (p. 106). 



f. Size smaller, bind foot of ^ about 26 fisheri (p. 115). 



g^. Color not gray, but dark or light umber or black. 



h^. Incisors abruptly decurved, inner groove conspicuous; color always 



black niger (p. 121). 



h^. Incisors conspicuously projecting beyond nasals, inner groove very 

 obscure; color not always black. 

 ^^ Color generally black (dark umber in a few individuals), 



orizabse (p. 90). 

 1*2. Color dark or light umber (black in a few individuals). 

 Color dark umber. 



h^. Feet, tail, and belly almost naked atrovarius (p. 95). 



Feet, tail, and belly with normal covering of hair. 

 I ^. Skull very short and wide; color very dark, 



umbrinus (p. 89). 



I 2. Skull less short and wide; color bright, .peregrinus (p. 91). 

 f. Color light umber sheldonl (p. 93). 



Description and Distribution of Species and Subspecies. 

 Thomomys bulbivorus Group. 



THOMOMYS BULBIVORUS (Richardson). 



Camas Pocket Gopher (Camas Rat of Richardson). 



(PI. II, fig. 1; PI. Ill, fig. 1.) 



Diplostoma hulhivorum Richardson, Fauna Boreali-Americana, I, 206, 1829. 

 Geomys bulbivorus Richardson, Ann. Rept. Brit. Assn. for 1836, VI, 150, 1837. 

 Ascomijs bulbivorus Wagner, Suppl. Schreber, III, 388, 1843. 

 Pseudostoma bulbivorum Audubon & Bachman, Quad. N. Am., Ill, 337, 1854. 

 Geomys ( Thomomys) bulbivorus Giebel, Saug. 530, 1855. 



Thomomys bulbivorus Brandt, Beit. Kennt. Saug. Russl., 188, 1855. — Allen, Bui. Am. 



Mus. Nat. Hist., V, 56, April 28, 1893.— Miller, Proc. Biol. Soc. Washington, 



VIII, 113, Aug. 6, 1893. 

 Thomomys [sub-genus Megascapheu^] bulbivorus Elliot, Field Columbian Mus., zool. ser, 



III, 190, May, 1903. 



Type. — Collected on Banks of the Columbia River, Oregon/' 

 probably Portland, the only place near the Columbia River where it 

 has since been taken. The type is said to have been in the Hudson 

 Bay Museum, but Oldfield Thomas writes (Mar. 15, 1915) that it 

 is not now in the British Museum collection. 



Distribution. — Willamette Valley, Oreg., from Portland and Forest 

 Grove south to Eugene; west to Grand Ronde (fig. 5). 



CJiaraeters. — Largest known species of the genus; hind foot of 

 adult male 40-43 mm.; front claws small and weak; external ear 

 merely a thickened rim; tail almost naked; winter coat long and 

 furry; summer coat short and harsh; color dark brown or sooty, nearly 

 concolor above and below; mammae in 4 pairs, inguinal 2-2, pectoral 

 2-2, with 4 separate mammary glands. 



