COTTUS — MILLER'S THUMBS 327 



depth caudal peduncle 1 . 5 to 2 in its length. Color "olivaceous, more 

 or less barred and specked with darker; fins mostly barred or mottled" 

 (Jordan and Evermann). All our specimens have evident oblique dusky 

 bars on posterior half of body. Head 3 to 3.5. convex above, the eyes 

 directed outward as much as upward; width of head almost as great as 

 its length; interorbital space 3.8 to 5.5; nose 2.8 to 3.4; mouth wide 

 and lips very thick, maxillary 1.7 to 2 . 1 in head, to middle of orbit; 

 upper preopercular spine short, usually less than half eye and rather 

 inconspicuous; lower spines concealed in skin; isthmus 1 .3 to 1 5 times 

 eye; palatines with teeth. Dorsal VII to IX, 16 to 18; first dorsal scarcely 

 f height of second; caudal spatulate; anal 13 to 15; pectorals to vent. 

 Body entirely destitute of scales; a few prickles, often indistinct, behind 

 pectorals; top of head warty; lateral line continuous or interrupted pos- 

 teriorly. 



This species inhabits clear, rocky brooks and lakes of the middle 

 and northern United States, ranging from Kansas and the Dakotas 

 to New York and Virginia. In our collections, which number 10 in 

 all, it has been taken only in northern and southern Illinois: once in 

 McHenry county ; once from the Du Page near Joliet ; six times fr< im 

 rocky spring branches in Union county ; and once each in springs in 

 Calhoun and Jersey counties. 



About 25 per cent, of the food of six specimens taken in southern 

 Illinois consisted of small fishes. Aquatic larvas formed about 40 

 per cent, of the food, and the rest was mostly Crustacea (Asellus). 

 In the clear streams and lakes of the north this fish has been found 

 to be extremely destructive to the eggs and fry of trout. 



COTTUS RICEI Nelson 



Nelson, 1S76, Bull. 111. State Lab. Nat. Hist., I. 1, 40. 



J. & ('».. 694 (Uranidea spilota) and 935 (U. ricei) ; M. V., 148; J. & E., II, 1952; J., 

 50 (Tauridea spilota); L., 30. 



Length (of <>ur single specimen) 2\ inches; body rather slender, regu- 

 larly tapered to the very slender caudal peduncle; depth 4.9; width 

 about same as depth; depth caudal peduncle 3.3 in its length. Color 

 (in spirits) brownish olive, sides irregularly and faintly mottled; faint traces 

 of 2 dusky bars on caudal peduncle ; last membranes of second dorsal dusk v . 

 Head very flat above, the eyes directed nearly upward; width of head 

 equal to its length; interorbital space flat, very narrow, 8.2 in head; 

 nose 3.6, the posterior nostril with conspicuous raised edges, tube-like; 

 mouth narrow, smaller than in last species, and lips thinner, the maxil- 

 lary scarcely past front of orbit, 2 . 9 in head ; preopercular spine long, § 

 of eye*; lower preopercular spines short and mostly concealed; the upper 

 spine hooked backward and upward, carrying with it the skin of the head 

 in an auricular flap-like appendage, giving the fish a buffalo-like appear- 



*Equal to eye, according to Nelson. 



