278 THE SEA SHORE 



different in form from the corresponding limbs of the lobster, will 

 be seen to resemble them closely in arrangement and structure. 

 The exo-skeletons of these creatures are, however, generally 

 hardened by a horny substance (chitiri) instead of a stony deposit 

 of carbonate of lime. 



The shrimps and prawns sold for food in our markets are very 

 similar in appearance when alive, the leading distinguishing 

 feature being, perhaps, the presence of a sharp, serrated beak 

 projecting forward from the front portion of the carapace of the 

 latter. 



The reader is probably acquainted with the fact that the shrimps 

 and prawns used as food have quite a different appearance when 

 alive and in their native element to that displayed by the corre- 



Fio. 210. THE COMMON SHRIMP (Crangon vulgaris) 



spending wares in the fishmonger's shop a fact that applies equally 

 well to the edible crabs and lobsters. Most crustaceans change to 

 a bright red colour when boiled, and, as stated in a previous chapter, 

 the same result is produced by the action of strong spirit. 



The Common Shrimp (Crangon vulgaris) is an exception, how- 

 ever, for it may be distinguished when boiled by its dull greyish 

 brown colour. "When alive this species is of a very pale greenish 

 or greyish tint, lightly spotted with brown ; and its habits are so 

 interesting that it will well repay one to watch it either in the 

 aquarium or in a rock pool. It frequents sandy coasts, and can 

 hide itself very quickly by burying its body in the sand, using for 

 this purpose both its legs and its antennae. 



The Prawn frequents rocky coasts, where it may often be 

 obtained in large numbers by sweeping with a suitable net under 



