142 



FIRST BOOK OF ZOOLOGY, 



obtained. The tail will be found flattened against the under 

 side of the body. Another species occurs in the salt-water 

 mussel. 



In the female crab, a figure of which is given (128), 

 this part is very large and will be oftentimes found holding 

 a mass of eggs. With care the creatures may be dried, 

 and their various parts separated and stuck upon cards for 

 the cabinet. 



FIG. 132. HERMIT-CRAB IN THE SHELL OF A SEA-SNAIL. 



131. The hermit-crab possesses the general features of the 

 common crab and lobster. The abdominal portion is long 

 and cylindrical, and, instead of being encased in a hardened 

 shell as in the lobster, it is soft and pliant, with scarcely a 

 trace of hardened parts to indicate the segments. The creat- 

 ure, having this defenseless part, protects itself by securing 

 the hard shell of some sea-snail as a house in which it con- 

 stantly lives. The caudal appendages are curiously modified 



