Fish-Hatching in a Current of Water. 119 



head, into a perfectly formed and shapely 

 fish. 



When the umbilical sac is absorbed, the 

 young salmon is called a parr, and already 

 the transverse bars may be seen on the sides 

 of the fish, which continue to distinguish the 

 parr until it reaches the smolt stage. These 

 bars are common to most, if not all, the 

 varieties of trout and salmon, which at this 

 early stage are very similar in appearance, and 

 are most difficult to distinguish from each 

 other. The migratory species, however, have 

 a larger number of bars than the non-migra- 

 tory. 



Although the alevins do not require much, 

 or any, food until the umbilical sac is absorbed, 

 it is wise to begin to offer them some a little 

 before that stage is reached by the earliest 

 hatched amongst them; otherwise, should 

 they get ravenously hungry before food is 

 offered, some may get too weak, and perish 

 without being able to partake of the unaccus- 

 tomed food, or they may gorge themselves, 

 causing illness, heavy losses being the result. 

 The food which it is most convenient to use, 

 and which answers exceedingly well, is the 



