120 UTILIZATION OF MINUTE LIFE. 



History of Animals. The common crawfish thrives 

 best in rivers, in holes in the banks, and under 

 stones, where it awaits the small mollusca, fishes, 

 larvae of insects, and other animal matters, upon 

 which it feeds. The curious old writer, Jerome 

 Cardan, tells us that this animal is a sign of the 

 goodness of the water in which it is boiled, for the 

 best water turns it very red, an absurd notion, 

 like many emanating from this and other similar 

 writers on medicine and natural history in the dark 

 ages of superstition. 



Desmarest assures us that a crawfish will live 

 for twenty years or more, and that it becomes 

 larger in proportion to its age. Towards the end 

 of spring it casts off the pieces which form its shell, 

 but in the course of a few days becomes again 

 covered with a solid coating as hard as the previous 

 one, and one-fifth larger. Sometimes this moulting 

 takes place at the end of summer ; it appears to 

 depend entirely upon the locality the animal lives 

 in, as it is seen to occur at different seasons in 

 different localities. Its eggs are carried for some 

 time under the abdomen, like those of the lobster. 

 The crawfish is taken in various manners, either by 

 nets or bundles of thorns, in which flesh in a state 

 of decomposition is placed, or by inserting the hand 

 into the holes it inhabits. 



By rearing these Crustacea artificially, M. Gerbe, 



