Some Friends in Armor 93 



The hermit crab lives long, indeed, if he survives the 

 attacks of enemies and the dangers of parasitism for 

 four summers' duration; but seldom does his life bear 

 so extraordinary a charm. During the earlier part of 

 this period he molts at least once — and sometimes, 

 though rarely, twice — a year. Each molt is accom- 

 panied by an increase in size; and as a consequence he 

 is obliged to find a larger shell. This shell needs never 

 to be wanting for long. He has but to choose almost 

 at random from the abundant supply around him, to 

 find one suitably roomy. Yet times innumerable have 

 I witnessed the abandonment of one for another, and 

 for no apparent purpose other than to satisfy a 

 crotchet. Moreover, he is not overscrupulous in the 

 selection he finally does make. With so many to choose 

 from, it would appear that instinct, if not reason, would 

 determine the proper choice and impel him to select 

 only that kind best fitted for his comfort and protection. 

 He will, nevertheless, abandon a specimen which for 

 convenience and capacity leaves nothing to be desired, 

 and wedge himself into another so small, that there is 

 scarcely space enough to retract his fore body in time 

 of extreme danger; in truth, he will adopt with equal 

 facility the covering of a perfect shell or a fragmentary 

 portion that passes as such. 



Few instincts are more strongly developed than the 

 instinct of self-preservation; in the crab, however, this 

 instinct, exemplified by his preferences for protective 

 coverings, shows some strange, aberrations. I have 

 found him encased in crumbling shells of rotten chalk. 

 In a piece of spongy bone. In a bent ferrule from a 

 jointed fishing pole, in a cumbersome hollow stone, In 



