202 CLASS CRUSTACEA. 



BiPELTATA, 



Has the testa divided into two bucklers, of which the ante- 

 rior, very large, more or less oval, forms the head, and the 

 second, corresponding to the thorax, transverse, and angular 

 in its outline, carries the jaw and ordinary feet. These feet, 

 with the exception at most of the posterior two, and the last 

 two jaw-feet, are slender, filiform, and for the most part very 

 long, and accompanied with a lateral ciliated appendage. 

 The four other jaw-feet are very small, and conical. The 

 base of the lateral antennae presents no scales. The middle 

 are terminated by two threads. The ocular pedicles are long. 

 The body is very much flatted, membranous, and transparent, 

 with the abdomen small, and without spines at the posterior 

 fin. 

 This family comprehends but a single genus, that of 



Phyllosoma, Leach. 



All the species belong to the Atlantic Ocean and the Eastern 

 Seas. With reference to their nervous system, they seem to 

 be intermediate between the antecedent Crustacea and those 

 which follow. 



OF THE MALACOSTRACA, WITH SESSILE AND 

 IMMOVEABLE EYES. 



The branchipes will be, from this point, the only Crustacea 

 which present us with eyes carried on pedicles ; but besides 

 that these pedicles are not articulated, nor lodged in special 

 cavities, these Crustacea have no carapace, and are also re- 

 mote from the preceding by many other characters. All the 

 malacostraca of this division are alike destitute of carapace. 

 Their body, from the head, is composed of a series of articu- 



