FISH OF ONTARIO. 59 



(67) Long-jaw Herring. Lake Herring. 



( Argyrosomiis prognathus. ) 



Body oblong, much compressed, back elevated, the bod}' tapering 

 rather sharply toward the narrow caudal peduncle ; the adult- ha\ ing a 

 slight nuchal hump as in C. clupeiformis ; mouth large and strong ; snout 

 straight, its tip on a level with the lower edge of pupil ; mandible very 

 long, projecting beyond upper jaw when the mouth is closed ; reaching to 

 or beyond posterior edge of the eye ; head rather short, deep and pointed ; 

 cranial ridges prominent, dorsal rather high ; origin of dorsal nearfer tip of 

 snout than base of caudal. Scales rather large, about seventy-five in 

 lateral lino; seven or eight above the lateral line; seven or eight below the 

 lateral line. Lateral line straight except at origin, where it presents a 

 rather marked cur\e. 



Colour, sides of body uniformly bright silvery, with pronounced bluish 

 reflection in life ; back dusky ; under parts pure white, without silvery. 

 Above the lateral line the upper and lower edges of the scales finely punc- 

 tulate with dark, the central part unmarked, producing light longitudinal 

 stripes extending whole length of body. Fins flesh colour or pinkish in 

 life, the dorsal and caudal usually showing duskv edges ; postorbital area 

 with bright golden reflection ; iris golden, pupil black. 



D., 9 or 10; A., 10 to 12. 



Average length, about fifteen inches. 



This fish may readily be distinguished from any other white fish found 

 in the Great Lakes by the general form of its body, together with the very 

 long lower jaw. 



It is taken in all the Great Lakes except Lake Erie, from which as yet 

 no specimens have been reported. In Lakes Ontario and Michigan it is 

 particularly abundant, and is highly esteemed as a food fish. 



There is much difterence of opinion among fishermen as to the spawn- 

 ing time of the Long-jaw, which seems to extend over a prolonged period. 

 Fish with matured roe have been taken as early as May 17th, and ripe 

 fish have also been reported from Lakes Ontario and Huron late in June 

 and through July. Very little is positively known as to the location of the 

 spawning grounds of this species, though it is said that they are in deep 

 water. 



(68) Black-fin Whitefish. 



(Argyrosomus nigripinnis.) 



Body stout, fusiform ; head and mouth large ; lower jaw slightly 

 projecting ; back not arched, profile from occiput to origin of dorsal fin 

 very gently curved ; eye rather large ; teeth very feeble, but appreciable on 

 the maxillaries and tongue. 



D. 12 • A 12 



Scales on lateral line, 73 to 77, above lateral line nine or ten, below 

 seven or eight. 



