47i' THE SAND-HOPPER. 



SESSILE-EYED CRUSTACEA. 



OrR attention is now drawn to the second great group of crustaceans, called the Sessile- 

 eyed Crustacea, because their eyes, instead of being placed on footstalks, are seated directly 

 upon the shell. The body is divided with tolerable distinctness into three parts, for which the 

 ordinary titles of head, thorax, and abdomen are retained, as being more convenient and 

 intelligible than the ingenious and more correct, though rather repulsive, titles that have 

 lately been affixed to these divisions of the body. 



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 Crus- 

 tacea obtain any large size, an inch and a half being nearly their utmost limit in point of length. 

 Most of these animals reside along the sea-shores, 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. 



AMPHIPODA. 



The first order of the Sessile-eyed Crustaceans is termed the Amphipoda, a word derived 

 from the Greek, and signifying "both Mnds of feet," because they are furnished with limbs 

 for walking and swimming; whereas, in the Isopoda, or similar-footed crustaceans, the feet 

 are all of the same character. The females are in the habit of carrying their eggs under the 

 thorax, mostly between certain flattened appendages attached to the base of the legs. 



The next family is called by the name of Orchestidse, or Junipers, because they possess 

 the power of leaping upon dry ground. TI13 most familiar of these little crustaceans is the 

 well-known Saxd-hoppei:, or Sand-skipper, seen in such myriads along 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 numbers. 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 anything that is soft and capable of 

 decay, and seems to care little whether the food be of an animal or vegetable nature. Decaying 

 sea-weed is a favorite article of food, and wherever a bunch of blackened and rotting sea-weed 

 lies on the sand, there may be found the Sand-hoppers congregated beneath it, and literally 

 boiling out when the sea-weed is plucked up. 



Wherever there is sand, the Sand-hopper is to be found, even though no traces may be 

 perceptible; and an experienced shore-hunter will seldom fail in obtaining as many as he 

 wishes in the space of a few minutes. Even where the sand is extremely dry and level, and 

 seems unfit to nourish Sand-hoppers, these little creatures are often snugly ensconced beneath, 

 having burrowed deeper and deeper as the sand became dry. If a smart stamp of the foot 

 be given, a vast number of little holes will make their appearance, as if by magic. These are 

 the burrows of the Sand-hoppers, which have been made while the sand was still wet, and 

 over which a film of moist sand had formed itself. The shock caused by the stamp of the 

 foot breaks the dried films, and the hole is at once made apparent. 



To catch the Sand-hopper in fair chase is no easy task, but it can be captured without any 

 difficulty by simply digging up (he sand and throwing it aside. The Sand-hoppers seem so 

 bewildered with their sudden change, that they merely sprawl about listlessly, and can be 

 picked up at leisure. 



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 crustaceans to settle on her handkerchief, it was bitten to rags 

 when she took it up. It is very fond of worms, will eat any kind of carrion, and sometimes. 



