660 THE SHRIMP, THE PRAWN, AND THE SAND-HOPPER. 



"Sand-raisers." The small prawns are often confounded with the 

 Shrimps, and popularly called hy the same title. They can, however, 

 easily be distinguished from each other, the beak of the prawn being 

 lono- and deeply saw-edged, while that of the Shrimp is quite short and 

 smooth. 



Our attention is now drawn to a very large group of crustaceans, 

 called the Sessile-eyed Crustacea, because their eyes, instead of being 

 placed on footstalks, are seated directly upou 

 the shell. The body is divided with toler- 

 able distinctness into three parts, for which 

 the ordinary titles of head, thorax, and ab- 

 domen are retained as being more couveui- 

 ent and intelligible than the ingenious and 

 more correct, though rather repulsive, titles 

 The Shrimp {aangon vul- that have lately been affixed to these divis- 



garie). ions of the body. 



The Prawn {Palcsmon ser- They have no carapace, like the stalk- 

 ''"^"^'*" ■ eyed crustaceans, nor do they breathe with 



gills, but by means of a curious adaptation of some of their limbs. 

 None of the Sessile-eyed Crustacea attain any large size, an inch and 

 a half being nearly their utmost limit in point of length. Most of 

 these animals reside along the seashores, where they are of very great 

 use in clearing away the mass of dead animal and vegetable matter 

 which is constantly found in the sea. 



The little Sand-hopper or Sand-skipper is an example of the first 

 family, called by the name of Orchestidoe, or jumpers, because the 

 members of it possess the power of leaping upon dry ground. These 

 little creatures are seen in myriads along all our sandy shores, leaping 

 about vigorously just before the advancing or behind the retiring tide, 

 and looking like a low mist edging the sea, so countless are their num- 

 bers. Paley has a well-known passage respecting this phenomenon, too 

 familiar for quotation. 



The leap of the Sand-hopper is produced by bending the body and 

 then flinging it open with a sudden jerk — in fact, the exact converse 

 of the mode of progression adopted by the lobster and shrimp. The 

 Sand-hopper feeds on almost everything that is soft and capable of 

 decay, and seems to care little whether the food be of an animal or a 

 vegetable nature. Decaying seaweed is a favorite article of food, and 

 wherever a bunch of blackened and rotting seaweed lies on the sand, 

 there may be found the Sand-hoppers congregated beneath it, and lit- 

 erally boiling out when the seaweed is plucked up. 



The teeth of this creature are strong and sharp, as indeed is needful 

 for the tasks imposed upon them. The Sand-hopper will eat anything; 

 and on one occasion, when a lady had allowed a swarm of these little 



