226 NEW YORK STATE MUSEIUM 



is no shoreward migration in summer. It is to be noted alsO' 

 that the whitefish moves along the shore, and in some eases it 

 ascends rivers for the purpose of spawning. It is believed also 

 that when the feeding grounds of the whitefish are polluted by 

 mud, the fish temporarily seek other localities. There appears 

 to be a spring and summer migration likewise from lake to lake. 

 Spawning takes place during October, November and December, 

 on shoals or occasionally in rivers. The female is larger than 

 the male. According to the observations of George Clark, the 

 two sexes, in the act of spawning, frequently throw themselves 

 together above the surface, emitting the spawn or milt with 

 the vents close together. Spawning operations are most active 

 in the evening, are continued at night, and the eggs are de- 

 posited in lots of several hundred at a time. The number of 

 eggs in a fish of 7J pounds was 66,606; the average number 

 being nearly 10,000 for each pound of the female's weight. The 

 period of incubation depends on the temperature. The usual 

 time of distribution of the young is in March and April. The 

 very young are described as swimming near the surface and 

 not in schools. They are very active and soon seek deep water 

 to escape from their enemies. Their food consists chiefly of 

 small crustaceans. The adults subsist on the same food with 

 the addition of small mollusks. 



Growth. The only means of determining the rate of growth 

 of the whitefish is by artificial rearing. Samuel Wilmot had 

 young fish which were 5 inches long at the age of four months. 

 The growth under natural conditions must be even greater thani 

 this. Mr Wilmot, himself, has seen whitefish measuring 7 

 inches in December in his ponds. 



Enemies and diseases. ' The eggs of the whitefish are destroyed; 

 in immense numbers by the lake herring, Coregonus 

 a r t e d i . The water lizard, Menobranchus, also con- 

 sumes vast numbers of the eggs. The young whitefish are eaten 

 extensively by the pike perch, black bass, pike, pickerel and fresh- 

 water ling. The lake trout also feed on the whitefish. A leach 

 parasitic on the whitefish proves very troublesome to that spe> 



