226 ANIMALS OF THE SEASHORE 



the shell of a sea snail and inserts its abdomen there- 

 in. These hermit crabs move about very rapidly, 

 carrying' their "houses" on their backs. 



As the hermit grows, his house becomes too 

 small for him, and it is necessary for him to seek a 

 new one. The hermit often encounters trouble in 

 this home-seeking task, for two crabs may choose 

 the same house ; as a consequence, there is a fight and 

 the victor takes the house while the loser is forced 

 to continue his search elsewhere. At times a home- 

 less hermit crab may attack and dispossess another 

 crab which happens to have a desirable home. 



These crabs are very abundant on the bottom of 

 the ocean off the New Jersey coast; they are also 

 frequently found in tide pools along the beach. It 

 is amusing to collect some and watch their antics in 

 a small glass dish or aquarium. 



This species usually inhabits shells of Nassa, 

 Urosalpinx, Eupleura or other small gastropods. The 

 shells are frequently covered with the hydroid 

 Hydrad in ia echlnata. 



Very common Massachusetts to Florida. 



Pagurus pollicaris Say (Big Hermit Crab) 



PLATE XXV. Fig. 9, 10 



Larger than the above and with broader hands ; 

 usually bright in color and covered with hairs. In- 

 habits shells of Fulgur and Polinices. Common with 

 the above, but more apt to be found off shore, al- 

 though frequently found stranded on the beach. 

 Like the above they are often covered with Hydrac- 

 tinia. Common from Massachusetts to Florida. 



