644 MALACOSTRACA. 



Western Europe, Cancer pagurus, (Gr. pagouros, a crab,) some- 

 times attains a large size, weighing ten or twelve pounds. It 

 casts its shell between Christmas and Easter. 



The CORIMON EDIBLE CRAB of the "United States, Lupa has- 

 tata, (Lat. from hasia, a spear,) is of smaller size. In forty- 

 eight hours after the old shell is cast, it is renewed and firmly 

 consolidated. In the interval, these Crabs are termed "Soft- 

 shelled," and eagerly sought after. They are abundant in the 

 muddy shores of bays and inlets. 



LONG-TAILED CRUSTACEANS. 



(2) The Macroura, (Gr. long-tailed.) are so named from the 

 large and well developed tail, ending in a fan-shaped fin, which 

 assists them in swimming. They walk well, but are best adap- 

 ted for swimming, shooting backwards through the action of the 

 abdomen and the tail fin. The antennae are usually long, the 

 first pair not being received into a cavity as in the Crabs. 



The Palinurus, is a large crab, shaped much like a lobster, 

 but is more cylindrical with none of the feet cheliform or claw- 

 like. It is armed with a very hard crust, and is in general use 

 when in season, as an article of food. Prof. Dana, (Silliman's 

 Journal.) speaks of two gigantic species of this genus, P. vulgaris, 

 of the Mediterranean, (see Chart,) and P. lalandii, of the Cape of 

 Good Hope, each a foot and a half long, independent of the an- 

 tennae. The COMMON PRAWN, Palamon vulgaris, found near 

 our coasts or at the mouths of rivers, is nearly allied to the 

 Prawn of England, P. serratus, (Lat. saw-shaped ;) these are 

 esteemed a great delicacy ; also allied to the species P. squiUa, (a 

 prawn,) of the European continent. The Common Prawn is 

 not more than an inch and a half in length ; but the RIVER 

 Prawn of the Carolinas and Florida, P. jluviatilis^ is seven or 

 eight inches long. 



The RIVER CRAY or CRAW FISH, Astacus, (Gr. astakos, a 

 kind of lobster. )jluviatilis, (Plate XVI. fig. 3, with explanation,) 

 may be regarded as the Fresh Water Lobster. It is found in 

 the fresh waters of Europe and the north of Asia, placing itself 

 in holes of the banks, or under stones, where it lies in wait 

 for small mollusks, little fishes, the larvae of insects and decom- 

 posed animal substances upon which it subsists. It is said that 

 it will live for upwards of twenty years, and becomes large in 

 proportion to its age. The eggs, when laid, are collected under 

 the lower part of the body or tail ; the young, which at birth are 

 very soft, take refuge under the tail of the parent for some days. 





