178 University of Washington Publications in Biology [Vol.2. 



35a. Anal rays 18; soft dorsal 21. Range: Lost River, 

 tributary to Klamath Lake, Oregon. Freshwater. 

 Not common. 

 245. Cottus evcrmanni Gilbert 



35b. Anal rays 10 to 15, soft dorsal 15 to 20 (usually 

 15 to 19) ; depth in the length 3.5 to 5.5. 



36a. Posterior nostril not at all tubular ; anal rays 

 11 to 14 (usually 12 or 13) ; body smooth; cau- 

 dal vertebrae 20 to 23. Range : East of Cas- 

 cade Mountains in the Columbia River drain- 

 age and south to Lake Lahonton. Freshwater. 

 Common. 



Smooth Bullhead 246. Cottus bcldingii 



Eigenmann and Eigenmann 



36b. Posterior nostril tubular. 



37a. Caudal vertebrae 20 to 23 (usually 21 or 22). 



38a. Anal rays 11 or 12 (seldom 13) ; soft dor- 

 sal rays 16 or 17. Range : Tributary of 

 Clearwater River near Bovill, Idaho. 

 Freshwater. Not common. 

 . .247. Cottus tubulatus Hubbs and Schultz 



38b. Anal rays 13 to 16 (usually 15) ; soft dor- 

 sal rays 17 to 20 (usually 19). Range: 

 Klamath River system, Oregon. Fresh- 

 water. Not common. 

 248. Cottus klamathcnsis Gilbert 



37b. Caudal vertebrae 25 or 26; anal rays 12 to 

 16 (usually about 14) ; dorsal rays usually 

 about 18 or 19. Range : Coastal streams 

 from Unalaska to Monterey, California. 

 Freshwater. Common. 

 249. Cottus aleuticus Gilbert 



34b. Preopercular spine single at angle, and 1 or 2 be- 

 low ; posterior nostril not tubular. 



39a. Depth in length 7 times ; pelvics I, 3. Range : 

 Upper Klamath Lake, Oregon. Freshwater. Not 

 common. 

 250. Cottus tenuis (Evermann and Meek) 



39b. Depth in length 4 to 5.5 ; caudal vertebrae 21 to 

 23 (usually 22 or 23). 



40a. Pelvics I, 4; anal rays 14 to 17 (usually 15 

 or 16) ; soft dorsal rays 17 to 20 (usually 18 

 or 19). Range: Alaska to California. Fresh- 

 water. Common. 

 Bullhead 251. Cottus gulosus (Girard) 



40b. Pelvics I, 3; anal rays 14 to 16 (usually 15) ; 

 soft dorsal rays 17 to 19, (usually 18). Range: 

 Mill Creek and Walla Walla River, Washing- 

 ton. Freshwater. Common locally. 

 252. Cottus marginatus (Bean) 



