Crustacea. 



6687 



forms merely brush and protect the mouth, in the lower fulfil the 

 office of hands, and supply the mouth with food. 



The hands of the crabs belong to the third pair of legs, and but 

 little fulfil the duty of such, except when climbing over some uneven 

 rock or surface. They are developed into a finger and thumb claw, 

 and have the power of firmly grasping any substance. In supplying 

 themselves with food the claws are very efficient organs ; but they 

 are somewhat differently used by some than others : the crab is 

 more gluttonous in its character, and snatches the food to its mouth 

 and greedily devours it ; not so the graceful prawn and curious 

 soldier-crab. 



Look in the vivarium, and see the transparent prawn. Look how 

 it holds the mass of food in one hand, and tears off small pieces with 

 the other, which it lifts to its mouth and eats, not in a crab-like man- 

 ner, but in a quiet, easy, comfortable way, as if it knew how to enjoy 

 an agreeable occupation ; nor is it so selfish but that another, with- 

 out raising its anger, may snatch a piece away ; but the stranger 

 must not take too much. What gentleman likes to lose his dinner ? 



But the soldier-crab I have most watched, and look upon as a par- 

 ticular pet. It lives in the shell of a dead mollusk, which it occupies 

 and carries about as a tenant-at-will. It has one of its claw-formed 

 arms longer than the other ; with the shorter, which in most spe- 

 cies is the left, it holds its food, and with the right he tears it away 

 piece by piece and puts it into his mouth. But this sociable indi- 

 vidual does not often dine alone : Mr. Gosse, in one of his pleasant 

 sea-side books, tells us how his meal is shared by a beautiful nereid 

 worm. The soft and serpent-like annelide smells the repast that the 

 master of the house is enjoying, and, like a wily guest, takes care 

 to be present at the meal, even though unbidden. See ! beneath 

 the crab the beautiful head glides out. While the self-confident 

 owner is devouring one piece, and in his full enjoyment looking 

 round and perhaps admiring the submarine scenery, the worm attacks 

 that which is in the other hand ; a little and little the crab feels it 

 going, and makes an effort to stop it on the way ; but it evidently can 

 be seen, by his manner, that he cannot believe that any one would be 

 so rude as to steal his dinner out of his very mouth, and does not 

 think much about the undevoured food, but which nevertheless is 

 slowly, gradually and surely taken away. 



Did the reader ever hold a handkerchief or any other thing firmly 

 in his hand, determined that the object should not be lost, and 

 after some time has looked down and perceived that it was gone ? 



