April, 1910. Fishes of Chicago — Meek and Hildebrand. 331 



Boleichthys fusiformis (Girard). Spindle-shaped Darter. 



Head 3.5 to 4.1; depth 5.8 to 7.1; D. ix or x — 10 to 12; A. 11, 

 6 or 7 ; scales 48 to 54. 



Body elongate, slightly compressed; head with bluntly pointed 

 snout; interorbital space narrow, convex; mouth small, horizontal, 

 its cleft 3.1 to 3.8 in head; lower jaw the shorter; maxillary reaching 

 past front of eye; snout blunt, 4.3 to 5.2 in head; margin of upper 

 lip on level with lower margin of eye; eye 3.5 to 4.0 in head; gill 

 membranes scarcely connected; spinous and soft dorsals usually 

 separated by a distance nearly equal to diameter of eye; separation 

 of ventrals about half their width at base; cheeks and opercles fully 



m. 



^-■f. 



Fig. 74. Spindle-shaped Darter. 



Boleichthys fusiformis (Girard). (From Forbes and Richardson.) 



scaled; nape usually with scales; breast naked or nearly so; belly 

 covered with ordinary scales; lateral line incomplete, absent on 25 

 or 35 scales. 



Color olivaceous, much dotted and blotched with brown, the dark 

 color in more or less definite W and X-shaped markings, or in zigzag 

 streaks ; spinous dorsal faintly dusky near base ; soft dorsal and caudal 

 faintly barred; males usually darker, with 9 or 10 transverse bars in 

 breeding season, and with basal third of membrane of spinous dorsal 

 jet-black, the fins edged with dusky. 



Length 2 to 2X inches. 



This fish ranges from Minnesota to Massachusetts and the Rio 

 Grande. 



Genus Microperca Putnam. 



The Least Darters. 



Body robust, slightly compressed; mouth small, its cleft nearly 

 horizontal, premaxillaries not protractile; ventral surface covered 

 with ordinary scales; gill membranes scarcely connected. 



