102 UNIVERSITY OF COLORADO STUDIES 



the anterior margin of the eye; maxillary never extending behind the eye; pre- 

 maxillaries protractile; lower jaw very slightly longer than the upper; spinous 

 and soft dorsals narrowly united, the soft dorsal the higher, spinous dorsal of X, 

 rarely XI spines, soft dorsal of 13 to 15 rays; pectorals about 1.5 in the head; 

 ventrals slightly smaller than the pectorals, base of the ventral spine on a level 

 with the last ray of the pectoral; anal short, the length of its base less than that 

 of the soft dorsal; anal spines III, rays 10 to 12 ; caudal peduncle broad, somewhat 

 upturned; caudal fin slightly notched; scales moderately large, feebly ctenoid, or 

 rarely cycloid in the anterior portion of the body, becoming strongly ctenoid 

 posteriorly; scales 10 to 12, 66-80, ig to 21; lateral line prominent, strongly arched 

 dorsally; scales in about 17 rows on the cheeks. 



General color olivaceous with a silvery luster, dorsal parts darker, body above 

 the lateral line with numerous faint, irregular, wavy streaks of dark olive-green; 

 color shading to grayish or greenish white below; body below the lateral line 

 crossed by twelve or more indistinct greenish bars; no distinct lateral stripe; 

 cheeks with five or more olive-green bars radiating from the posterior margin of 

 the eye, a greenish bar from the anterior margin of the eye extending to the tip 

 of the snout; eye dark reddish brown; fins uniformly greenish. Color somewhat 

 variable, bars and stripes more distinct in breeding females. 



The Small-mouthed Black Bass or Tiger Bass excells the Large-mouthed 

 Black Bass in the fighting qualities which make it so highly prized as a game fish. 

 It is, however, a smaller fish than the latter and is restricted to colder and clearer 

 water than that in which the Large-mouth may be found. The maximum size 

 reached by the Tiger Bass is about 5 pounds. 



Micropterus dolomieu ranges from southern Canada south into Arkansas. It 

 has been widely introduced in many states and is quite successful where conditions 

 are favorable. The only record obtained in the present study is from Canyon 

 City, where the Tiger Bass has been planted. 



Colorado specimen. — University Museum: Sells Lake, Canyon City, September, 1913 (90 

 mm.), F. A. Reidel, No. 405. 



Family PERCIDAE 

 The Perch and Darters 



Spinous and soft dorsal fins separate; scales strongly ctenoid; mouth large; 

 species carnivorous; fishes of the fresh waters of the northern hemisphere. 



The North American species of Percidae may be divided into two groups on 

 the basis of size. The few large Percids include some of the favorite game and 

 food fishes of the northern lakes, the Wall-eyed Pike, the Sanger and the Yellow 

 Perch. The small perch are known as Darters, of which about one hundred species 

 are recognized. These little fishes inhabit the small brooks and rapidly moving 

 streams, avoiding the warm and stagnant waters. Most of the Darters are quite 



