314 CRUSTACEA. 



GAMMARUS, Fab., 



Which is now divided into various subgenera, such as Phronima, Hyperia, 

 &c. Among the most interesting of these is the 



COHOPHITTM, Lat. 



The C. longicornis, called Pemys, on the coast of Rochelle, lives in holes, 

 which it forms in the mud, that is covered with hurdles, called louchots by 

 the inhabitants. The animal does not make its appearance till the begin- 

 ning of May. It wages everlasting war against the Nereides, Amphinomse, 

 Arenicolae, and other marine Annulate, which inhabit the same locality. A 

 curious spectacle is presented by these Crustacea when the tide is coming 

 in? myriads of them may then be seen moving in every direction, beating 

 the mud with their great arms, and diluting it in order to discover their prey: 

 is it one of the above mentioned Annulata they have discovered, which 

 is ten or twenty times' larger than themselves? they unite to attack and de- 

 vour it. The carnage never ceases until the mud has been thoroughly 

 turned up and its inequalities levelled. They do not even spare Mollusca, 

 Fishes, or dead bodies on the shore. They mount upon the hurdles which 

 contain Muscles, and fishermen assert that they will cut the threads that 

 keep them there, in order to precipitate them into the mud, where they may 

 devour them at their leisure. 



ORDER IV. 



L^EMODIPODA.(l) 



The Lsemodipoda are the only Malacostraca with sessile eyes, in 

 which the posterior extremity of the body exhibits no distinct bran- 

 chiae, and which are almost deprived of a tail, the two last feet be- 

 ing inserted in that extremity, or the segment which connects them 

 with it being merely followed by one or two very small joints. They 

 are also the only 'ones in which the two anterior feet, that corres- 

 pond to the second foot-jaws, form part of the head. 



They all have four setaceous antennas supported by a triarticu- 

 lated peduncle, mandibles without palpi, a vesicular body at the 

 base of at least the four pairs of feet, beginning at the second or 

 third pair, those of the head included. The body, usually filiform 

 or linear, is composed of eight or nine segments, including the head 

 and some small appendages in the form of tubercles at its posterior 



(1) Throat-footed. 



