64 



AMERICAN FISH CULTURE. 



By comparing the top with the bottom line of this table, 

 the reader will observe the large difference in the develop- 

 ment of the embryo and fetus, and the term of incubation 

 of water at 37° and at 54°, as well as the difference in the 

 time occupied by the young fish in absorbing the umbilical 

 sac and beginning to take food. The time of incubation 

 is five times as long at 37° as it is at 54°. 



During the time of hatching the fish culturist should 

 examine his troughs daily, removing the addled eggs, which 

 can be easily detected from their being perfectly white and 

 opaque. A record of the estimated number of eggs 

 deposited should be kept, and the number of bad eggs taken 

 out also noted, so that the percentage of loss in incubation 

 can be arrived at after that process is completed. Every 



