CHAPTER XVII 

 SAND-HOPPERS 



WHEREVER there is a sandy seashore with here 

 and there masses of dead seaweed and coral- 

 lines thrown up by the waves, you will find sand-hoppers 

 feeding on the debris. They are crustaceans, like crabs, 

 shrimps, and barnacles, but in general aspect resemble 

 enormous fleas. I hope that this comparison will not 

 enable any reader at once to picture the less familiar 

 by the more familiar. A good-sized sand-hopper is 

 about half an inch long, and jumps not by means of a 

 specially large pair of legs as the flea does, but by the 

 stroke of the hind body, the jointed rings of which are 

 carried curled downwards and ready to give a sudden 

 blow. The sand-hopper (Fig. 20, a) has some of the rings 

 or segments of the mid-body distinct, and not fused with 

 those of the head or overhung by a great shield as in 

 the lobster, crab, and shrimp. His walking legs and 

 jaw-legs are also not quite of the same shape, though 

 similar to those of a lobster, and his two little black 

 eyes are not mounted on stalks, but are flush with the 

 surface of the head. There are two quite distinct kinds 

 of sand-hopper which live in crowds together on our 

 sandy shores. They are not very different, but still are 

 distinguished by naturalists from one another ; one is 

 called Talitrus (Fig. 20, a), the other Orchestia (Fig. 20, b). 



They are very similar in appearance and structure to a 



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