THE CRAYFISH 



135 



bunches of eggs fastened to the appendages beneath the abdo- 

 men. These eggs or " berries " are laid during the month of 

 April, and become attached to the abdominal appendages (the 

 swimmerets) by a sticky secretion. They are carried about 

 and thus protected by the mother until they hatch; then the 

 young still cling to their parent for about two weeks, after which 

 they lead a separate existence. The life of a crayfish extends 

 over a period of about three years. Many crayfishes are de- 

 stroyed by man, by otters and minks, by fish, and by king- 

 fishers, but the eggs and young are well protected, the continued 

 existence of the race thus being assured. 



FIG. 76. Cotton field damaged by crayfishes after three plantings. (After 



Fisher.) 



Relations to Man. Crayfishes, as mentioned above, may 

 scmetimes be " farmed " in order to supply the demand for food 

 which cannot be satisfied by the lobster industry. At the pres- 

 ent time, however, they are of very little value from this stand- 

 point. 



