44 FISHES OF ILLINOIS 



sissippi and the Ohio, as many as a thousand pounds at a time 

 having been caught, according to Mr. Ashlock, from the former 

 river near Alton and the latter at Cairo. This species ranges from 

 the Ohio through the Great Lake region to the Saskatchewan, 

 becoming especially abundant in Manitoba and other parts of 

 British America. Our nine collections came from the Illinois 

 River at Meredosia and Havana, excepting rine, which was from 

 the Ohio at Cairo. It is found only in our largest streams, and is 

 commonest in rather swift open water. It is readily caught when 

 plentiful by minnow bait, and is a ver}^ gamy fish, although of 

 little value as food. It lives mainly on both terrestrial and aquatic 

 insects, mollusks, and small minnows. It is said by Illinois fisher- 

 men to be frequently seen pursuing its minnow prey at evening in 

 the vicinity of their boats. 



HIODON TERGISUS Le Sueur 

 (toothed herring; mooneye) 



Le Sueur, 1818, J. Ac. Nat. Sci. Phila., I, 366. 



G., VII, 375 (Hyodon); ]. & G., 260 (Hyodon) ; M. V., 69; J. & E., I, 413; N. 44 

 (Hyodon); J., 54 (Hyodon); F., 74 (Hyodon); F. F., I. 2, 79, II. 7, 440; L., 20. 



Length 10 or 12 inches; body somewhat less 

 compressed than in the last species, greatest width 

 not over 2^ in depth; depth in length 3 to 3.3; 

 depth caudal peduncle 1.4 in its length. Color pale 

 olive-buff above with faint steel-blue luster; sides 

 silvery, lustrous, white at the ventral edge. Head 

 4 to 4.4 in length; width head 2 to 2.1; inter- 

 orbital space 3.9 to 4; eye 2.8 to 3.6 in head; nose 

 Fig. 12 4 to 5.5; mouth slightly smaller than in the last, 



maxillary falling short of middle of orbit, 2.1 to 2.5 



in head. Dorsal fin with 11 or 12 developed rays, inserted in front of 



anal. Scales 5 or 6, 55,.7 ; lateral line complete. 



The toothed herring — a name given this species by way of con- 

 trast with the "thread-herring" or gizzard-shad (Dorosoma) — has 

 been taken by us only some half dozen times in Illinois, and then 

 only in the Rock and Illinois rivers. It ranges from the Ohio 

 River north and west to the Lake of the Woods, the Assiniboin, 

 and the Saskatchewan. It is very abundant in Lake Erie and the 

 Ohio, where large numbers are sometimes caught with the seine. It 

 feeds on insects and their larvae, mollusks, and small minnows. 

 It is a vigorous biter, and gamy on the hook. Dr. Estes says that 



