-iS FISHES OF ILLINOIS 



of about 3 pieces, forming lateral margin of upper jaw; teeth usually small 

 or wanting, variously arranged; air-bladder large, with open duct. 



Species numerous (about 150 known), abundant and widely 

 distributed in all seas, usually swimming in immense schools. 

 Many species ascend fresh waters in spring to spawn and a few 

 are permanent residents in fresh water. Two genera are found 

 in streams tributary to the Atlantic and the Gulf and in the 

 Mississippi Valley. 



KEY TO THE GEXESA OF CLUPEID^ FOUXD IN ILLINOIS 



at a terse angle, so that the tip of the upper jaw does 

 in front at a very acute angle, ao that the emaiglnate 



front of the upper jaw lecettea the irtemicr tip of the lower; fore part of 

 cheeks very Jeep, deeper t^M Ions'; Ja-ws toothless . ................... AJosa 



GENUS POMOLOBUS BAPINESQUE 



ALK WIVES 



Body rather elongate, more or less compressed; belly sharp-edged, 

 strongly serrated before and behind ventrals; mouth terminal, oblique; jaws 

 about equal, the upper somewhat notched at tip; mandible shutting within 

 maxQlarieB; teeth feeble, variously placed; dorsal short, nearly median, its 

 posterior ray not prolonged in a filament; scales thin, cycloid. Species 

 numerous, mostly anadromous, inhabiting both northern and tropical seas; 

 one species found in fresh waters of the Misassipp: Valley. 



POMOLOBUS CHRYSOCHLORIS RAFINESQUE 

 GOLDEN SHAD: SKIPJACK: BLUE HEBBING 



: - 



J. Jb O, 2CC (Clupea): M. V, 73 (Clupea); J. * EL, I. 4*5; X, 44 (misspelled); J, 

 55: F, 73 (Clap* a); P. F, H. 1. 439; Lv, 20. 



Length 15 inches; body elongate, com- 

 pressed, greatest width somewhat less than 

 2> in dep'h in adults; depth 3.6 to 4.3: 

 depth caudal peduncle 1.4 to 1.6 in its 

 length. Color silvery to greenish with bluish 

 and golden reflections; back fight olive-gray 

 with strong bluish raster; sides fight ofive- 

 green, Adding to silvery white, with golden 

 ^^^p^pjB^B^^ raster; belly opaque milk-white; no dark 

 spot behind operde. Head pointed, 3.7 to 

 4 in length; width head 2.3 to 2.6 in its 

 length; interorbital space 5.8 *o 6i3 in head, less than eye; eye 4.5 to 5.9 in 

 eyelid pumeut; nose 4-3 to 5.2 in head, mouth large, terminal, 



