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well as that taken from a live fish. These experiments were made 

 with whitefish {coregonus alba) milt and ova — those of other species 

 may differ widely in susceptibility of impregnation or fertilization 

 after the death of the parent Statements are made that milt of 

 the trout kind has been shipped from California to Boston without 

 parting with its fertilizing inSuence entirely. 



Mr. Carpenter learned, furthermore, that when a single drop or 

 two of milt was all that could be obtained, and it'appearedthickish, 

 that the, fish was about exhausted and such milt contained con- 

 paratively few spermatozoa — hence it was almost worthless for the 

 purpose for which it was intended. But when the milt was in con- 

 siderable quantity and was very fluid, then it contained compara- 

 tively the maximum quantity of spermatozoa, and a single drop of 

 it would fertilize more ova than twenty drops of the thick. Both 

 milt and ova were entirely worthless if exposed to a temperature 

 below 31°. This degree of temperature appears to deprive the milt 

 of its fertilizing influences, and deadens the susceptability of the 

 ova of being fertilized. 



Many statements are made by fishermen and others to the effect 

 that the eggs ot fishes are often found frozen in ice on the shore or 

 banks of streams, as well as ponds and lakes, and afterwards 

 hatched successfully. 



Some experiments, carefully conducted by Mr. Carpenter, dem- 

 onstrate that whenever the eggs are subjected to a temperature 

 below 32° Fahrenheit, that vitality ceases. 



Statements have been found going the rounds of the press, to the 

 effect that fish have been found in the streams, frozen stiff, and 

 afterwards restored to life. All experiments made in this direction 

 have resulted in the absolute death of the subjects of the experi- 

 ments. Experiments made by us in fertilizing eggs after they were 

 extruded, resulted in showing that where five minutes were allow- 

 ed to elapse after the eggs were obtained, and before the milt was 

 applied, only four per cent, were impregnated, and of all those that 

 were left a longer time none were impregnated. 



