BOTTOM-OF-SEA INFLUENCE ON HERRING. 27 



days, while in warm they may take no more than 

 six days. In the Baltic, with its lower temperature, 

 it is said they do not leave the egg in less than forty 

 days. Referring again to the reports issued by the 

 United States Government, "The development of the 

 egg can easily be observed with the naked eye. As 

 soon as the little fish begins to form inside the egg, 

 the two eyes are distinctly seen in the otherwise trans- 

 parent egg, like two black dots." The body of the fish, 

 when hatched, is as transparent as the water, which 

 enables it to escape some of its argus-eyed foes. For 

 a time after being hatched the abdominal cavity is still 

 filled by what may be called the yolk, during which 

 time it requires no other food, but lies about at the 

 bottom, making curious little jerky movements. In 

 the course of a few days, when the yolk has been 

 absorbed, the little creatures begin to swim about in 

 shoals with wide-open mouths, eager to become better 

 acquainted with their portion of the universe, which 

 they find in the embryo of gasteropods, etc., with which 

 they quickly fill themselves for near their whole length. 

 When they have passed their first stage, which may 

 be called the larva, that is, the " baby," they begin to 

 put on their shining silver armour; but being yet 

 only juveniles, and everything new to them, they keep 

 the even balance of their scales by deserting the now 

 dangerous shallow waters for the deeper seclusion of 

 their progenitors. Here the gay young knights 

 develop into the " middle form," at which time they 

 are generally very fat. From this they are promoted, 

 by the law of seniority, to the rank known as " ma- 



