April, 1910. Fishes of Chicago — Meek and Hildebraxd. 333 



Genus Koccus Mitchili. 



Striped Bass. 



Body deep, compressed; mouth large, lower jaw the longer; no 

 supplemental maxillary; lower margin of preopercles serrate or entire; 

 base of tongue with i or 2 patches of teeth; dorsal fins separate; anal 

 spines 3. 



Roccus chrysops (Rafinesque.) Striped Bass. 



Head 3,1 to 3.4; depth 2.6 to 2.9; D. ix-i, 13 or 14; A. in, 11 to 

 13 ; scales 52 to 57. 



Body rather deep, compressed; the back elevated; head sub- 

 conical; interorbital convex, 3.4 to 4.1 in head; mouth terminal ob- 

 lique, maxillary reaching middle of orbit; lower jaw the longer; gill 

 rakers as long as the gill filaments; cheeks and opercles with 10 to la 

 rows of scales; lateral line usually complete. 



Color silvery, tinged with golden below; sides with narrow dusky 

 lines, about 5 above lateral line, one coincident with it, and a variable 

 number below it. 



Length 12 to 18 inches. 



This species inhabits the Great Lake Region and the Mississippi 

 Vallev north of Arkansas. 



Genus 3I<>roiie Mitchili. 



Body rather short, deep, compressed; no supplemental maxillary; 

 lower margin of preopercle serrate or entire; base of tongue without 

 teeth; spinous and soft dorsals connected by a membrane; anal 

 spines 3 ; scales ctenoid. 



Morone interrupta Gill. Yellow Bass; Striped Bass. 



Head 3.0 to 3.2; depth 2.7 to 2.9; D. ix-i, 12; A. in, 10; scales 



51 to 55. 



Body deep and compressed, the back elevated; head subcorical, 

 pointed, jaws about equal; interorbital space slightly convex, 4.0 to 

 4.7 in head; snout 3.1 to 3.7; mouth terminal, the maxillary barely 

 reaching to middle of the orbit ; gill rakers longer than the filaments ; 

 snout 3.1 to 3.7; dorsal fins connected; cheeks and opercles with 

 about 12 rows of scales; lateral line complete or nearly so. 



Color olive-buff to silvery; 3 dark lateral stripes above lateral line. 



