346 THE AQUARIAN NATURALIST. 



There is indeed something irresistibly comical in the 

 imperturbable demeanour of these hard-visaged ma- 

 rauders nothing can make them laugh no amount 

 of mischief done, or agony inflicted, for a moment 

 alters the grim, stolid countenance with which they 



sit, 



" Chattering their iron teeth, and staring wide 



With stony eyes," 



amid the havoc they have caused. A monkey in a 

 lady's boudoir, or a bull in a china-shop, could 

 scarcely prove less eligible inmates than these scram- 

 bling tyrants of the well-stored tank. Let the aqua- 

 riist, therefore, keep them carefully aloof from any 

 specimens of damageable nature. Nevertheless, the 

 study of their habits is by no means devoid of interest ; 

 and, under proper treatment, even these creatures 

 have been looked upon as pets, and regarded as ' ' little 

 dumb companions, having always something to 

 impart." 



One of the most remarkable phenomena connected 

 with the history of these Crustaceans is the periodical 

 exuviation or change of shell to which they are 

 subject, a change, the necessity for which must be 

 obvious when we consider the dense, unyielding nature 

 of the stony armour in which their bodies are encased. 

 That they must get rid of their old suit of mail when 

 it becomes too small for their increasing size is evident 

 enough ; but how this is to be accomplished is a 

 problem, the solution of which presents so many 

 difficulties, apparently insurmountable by any natural 

 process, that nothing short of actual observation would 

 warrant a belief in its being able to achieve a feat 



