THE WHITEFISH, SALMON AND TROUT 



Family XV. Salmonida 



THE characters of the Salmonidcc are well known and need 

 not be repeated here. As now restricted this is no longer one 

 of the large families of fishes, albeit it is one of the most im- 

 portant, and for beauty, activity, gaminess, quality for food, and 

 size of individuals, different members of the family stand easily 

 with the first among fishes. There are about 10 genera and nearly 

 loo species. 



The Salmonid<z are confined to the northern hemisphere, and 

 north of the 4Oth parallel they are nearly everywhere abundant 

 wherever suitable waters are found. Some of the species, espe- 

 cially the larger ones, are marine and anadromous, living and grow- 

 ing in the sea, and entering fresh waters only for spawning 

 purposes; still others live in running brooks, entering lakes or the 

 sea as occasion serves, but not habitually doing so; others again 

 are lake fishes, approaching the shore, or entering brooks in the 

 spawning season, at other times retiring to waters of considerable 

 depths. Some of them are active, voracious, and gamy, while 

 others are comparatively defenceless and will not take the hook. 



The large size of the eggs, their lack of adhesiveness, and the 

 ease with which they may be impregnated, render the members of 

 this family especially adapted to fish-cultural operations. 



The Salmon! d& are of comparatively recent evolution, none of 

 them occurring as fossils unless it be in recent deposits. The in- 

 stability of the specific forms and the absence of well-defined spe- 

 cific characters may in part be attributed to their recent origin, 

 as Dr. Giinther has suggested. 



The family contains 2 well-marked subfamilies, the Coregonince 

 (the whitefishes and lake herrings) and the Salmonince (the salmons, 

 charrs and trouts). 



Coregonince : 



a. Mouth not deeply cleft, the mandible articulating with the quadrate 

 bone under or before the eye; dentition more or less feeble 

 or incomplete; scales moderate or large. Species imperfectly 

 anadromous, or confined to lakes or rivers. 



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