ill THE SERVICE OF TAILS 6g 



the body, the other two braced themselves against 

 me and pulled on the tail with all their strength, 

 to uncoil it. We wrestled with it until we were 

 fairly exhausted, failed utterly, and gave up beaten. 

 Such was the wonderful power in the tail of that 

 small animal." 



As a receptacle and carrier of eggs the tail parts 

 of certain among the lower animals serve an im- 

 portant purpose in their economy. In the lobster, 

 and its miniature, the fresh-water crayfish, the 

 latter segments of the abdomen form a fan-shaped 

 tail, on the under surface of which are small ap- 

 pendages called swimmerets. When the eggs have 

 ripened between the ovaries of the female (whose 

 swimmerets are especially adapted to their purpose, 

 and different from those of the male), they are ex- 

 truded from openings in the second pair of legs, 

 just back of the great front claws. These eggs 

 are covered with a viscid matter, something like 

 those of the. frog, which is readily drawn out into 

 threads. These threads become entangled with 

 the hairs covering the swimmerets, and thus sev- 

 eral hundreds of eggs attach themselves to each 

 swimmeret, and appear as large grape-like bunches, 

 iilling the whole space beneath the tail. Here they 

 develop under the most favorable conditions, and 

 after the young have hatched, these hold on to the 

 swimmerets, and are carried about and protected 

 by the mother until they are able to care for them- 

 selves. Here is another caudal nursery. 



