20 



Couesius plumbeus (Agassiz). 



This species may be found in Illinois, but has not yet been taken. Similar to Semotilus. 



but with smaller scales. 



Platygobio pallidus Forbes (147b.— Misprinted in Appendix, 8th ed., as 

 P. gracilis.) 



A small silvery species, reaching a length pf S inches; barbel prominent. Differs from 

 the young of P. gracilis, with which it has been confused, in the shorter and broader head, 

 broader interorbital space, wider mouth, and shorter dorsal, anal, and pectorals. 



Found only in the Ohio River near Cairo, from which locality we have 21 specimens, the 

 largest of which are about 3 inches long. 



Family Anguillid^ (The Eels). 

 Anguilla chrysypa Rafinesque. — American Eel. (218) 



Ascending rivers from the sea, to which it returns to spawn in the deep water. Common 

 in large streams in spring. 



Family Hiodontid^ (The Moon-eyes). 

 Hiodon alosoides (Rafinesque). — Moon-eye. 



Known from the next by the strong carlnatlon of the belly both before and behind the 

 ventral fins. Dorsal fin with 9 rays, 

 A fish of the large rivers; no longer common in the waters of Illinois, 



Hiodon tergisus (Le Sueur).— Moon-eye; Toothed Herring. 



Belly not strongly carinate before the ventrals; dorsal fin with 12 rays. 



Occasionally taken from the Illinois and Mississippi rivers; formerly more abundant. 



Family DoROSOMiDiE (The Gizzard Shads J. 



Dorosoma cepedianum (Le Sueur). — Gizzard Shad; Hickory Shad: Skip- 

 jack. 



This fish will readily be recognized by the elongation of the posterior rays of the dorsal. 

 Very abundant in large streams everywhere, and occasionally taken from pools in small 

 streams. 



Family Clupeid^ (The Herrings). 



Pomolobus chrysochloris Rafinesque. — Skipjack; Blue Herring. (171) 



Not common, but only occasionally taken from large streams. Has been obtained by us 

 from the Illinois, Ohio, and Mississippi rivers. 



Alosa sapidissima (Wilson).— Common Shad. (172) 



Introduced into waters tributary to the Gulf of Mexico, and since taken from the Ohio 

 River at Louisville by Dr. Evermann, of the U, S. Fish Commission. 



Family Salmonid^ (The Salmon Family). 



■ Coregonus quadrilateralis Richardson. — Round Whitefish. 



Lake Michigan. 



Coregonus dupeijormis (Mitchill). — Common Whitefish, 



Lake Michigan, chiefly in deep water. 



Argyrosomus artedi (Le Sueur). — Cisco; Lake Herring. (186) 



Descending the canals from Lake Michigan to the Illinois River. One specimen taken at 

 Meredosia and three at Ottawa. 



