506 THE BLACK-CLAWED CRAB. 



the field, yet at other times he shews great timidity, 

 and is very expeditious in effecting his escape j if, 

 however, he be often interrupted, he will pretend 

 death, like the spider, and watch an opportunity to 

 sink himself into the sand, keeping only his eyes 

 above. 



In the under part of the shell a crescent-formed 

 suture may be observed, which opens at the cast- 

 ing of the shell, and leaves a space sufficient for 

 drawing out the whole body : the thorax soon after- 

 drops its breast-plate, and then the legs quit their 

 crustaceous coverings. The body is now only en- 

 veloped in a soft skin, not unlike wet parchment ; 

 and the animal is so helpless as for a while to be in- 

 capable of motion, but lies between the rocks till 

 it has acquired sufficient strength and hardness to 

 bear the weight of its body, and con% r ey itself 

 from place to place to perform its usual functions.. 

 The old shell is left, in tw r o divisions, one that co- 

 vered the body, and the other that inclosed the 

 legs. Dr. Darwin asserts that the stomach and in- 

 testines are also cast with the skin - 3 and that the first 

 food the animal takes after recovering its strength is 

 the old stomach. It sometimes happens that the 

 shell hardens prematurely, and fixes the animal a 

 prisoner in his crevice j for fishermen have often 

 found them thus immured. When Crabs are 

 out of health they do not change their shells regu- 

 larly, the old shells always remaining till they have 

 recovered their proper strength and vigour. 



When the fishermen take a crab that is not in 

 good condition they return it into the sea, and some- 



