164 FISHES OF ILLINOIS 



Taken by us in only three collections — from the Rock River at 

 Erie, from Green River at Cleveland, and from the Illinois River at 

 Naples. The first two came from fairly swift water running over 

 rock and gravel. The species is said to be rather common in 

 sandy river channels from Iowa and southern Illinois southward 

 to the Alabama River. It ranges also westward and northward in 

 the Missouri to Nebraska and Minnesota 



HYBOPSIS DISSIMILIS (Kirtland) 

 (spotted shiner) 



Kirtland, 1840, Bost. Jour. Nat. Hist., Ill, 341 (Luxilus). 



G., VII, 177 (Ceratichthys) ; j & G., 215 (Ceratichthys) ; M. V., 64; J. & E., I, 318; 

 N., 45 (Ceratichthys); J., 62 (Ceratichthys); F„, 74 (Semotilus) ; L., 19. 



Known from H. amblops, which, of our species, it most resembles, 

 by its more slender body, smaller eye, and more ,or less mottled coloration. 



Length 3 inches; body long and slen- 

 der, subfusiform, little compressed, 

 depth 4.7 to S . 3 in length; caudal 

 peduncle slender, about equal to the 

 head, its depth 2 . 3 to 2 . 8 in its length. 

 Color olivaceous, the sides silvery; 

 a more or less distinct bluish lat- 

 p IGi 42 eralband, most evident posteriorly, 



in places widened or broken into 

 blotches; back and sides marked with irregularly X-shaped splotches 

 formed by dark punctulations on the scales; a dusky band through eye 

 to end of snout; fins plain. Head somewhat long, flattish above, 3 .9 to 

 4.2 in length; its width 1 . 9 to 2.2 in its length; interorbital space 3.3 

 "to 3.9; eye 3.1 to 3 . 8, little elliptical ; nose 2 . 4 to 2 . 7 in head, bluntly 

 pointed and somewhat decurved, projecting little beyond the mouth; 

 mouth horizontal, inferior, tip of lower jaw as far in front of anterior nos- 

 tril as that is in front of eye ; length of maxillary 3.6 to 4.3 in head, 

 reaching to anterior nostril; barbel usually rather less than diameter of 

 pupil; isthmus wide, its breadth equal to diameter of orbit. Teeth 4-4, 

 with very narrow grinding surface ; intestine 1 to 1 . S times length of head 

 and body; peritoneum black. Dorsal fin with 8 rays, set distinctly in 

 .front of ventrals, and about equidistant between tip of snout and base 

 bf caudal ; longest dorsal ray 1 . 1 to 1.3 in head ; anal rays 7 ; pectorals 

 about f to ventrals; ventrals to vent. Scales S or 6, 38-47, 4 or 5 ; 14 to 

 17 rows before dorsal; lateral line complete, nearly straight. 



No females with eggs found in our collections, which are few, 

 and mostly taken in midsummer or after. Males with organs ap- 

 parently well developed, but without tubercles, taken in the mid- 

 dle of June. 



