DECAPODA. 183 



pedicles are susceptible of being entirely retracted within their fos- 

 sulae, and are protected posteriorly by a dentiform projection, or 

 angle, of tin- literal edges of the shell. The second joint of the pe- 

 duncle of the lateral antenna' is much larger than the following one ; 

 they are terminated by a very short stem resembling an elongated 

 sty let. 



>, Leach. 



Lateral edges of the shell dilated behind the ocular cavities, which 

 large and oval ; external side of the second joint of the lateral 

 antennae compressed and carinated; ocular pedicles, when erected, 

 entirely exposed. The body is sub -ovoid*. In the 



LIBINIA, Leach, 



The ocular fossuhe arc very small and nearly orbicular, and the 

 ocular pedicles are very short, and but very slightly exertile. The 

 ud joint of the lateral antennae is cylindrical, and uot compressed, 

 or hut vi iy ^lightly so. The body is nearly globular, or triangular. 



We will unite the Doclcea and the Egeria of Leach to his Li- 

 BINLE. 



In his Libiniae, properly so called f, the claws of the males are 

 thicker than the two following feet, and almost as long. The length 

 of the longest does not exceed twice that of the shell. 



The claws ,,t tin* male DoclaeaJ are much shorter than the two 

 following feet. The length of the latter is hardly more than once 

 and a half that of the shell, which is nearly globular and always co- 

 vered with a brown or blackish down. 



In the Egerhe the claws are filiform, and the hands much elon- 

 gated and almost linear. The following feet are five or six times 

 longer than the shell. The body is triangular. 



Having reviewed all the sub-genera of this tribe in which the feet 

 subsequent to the claws are of a similar form, and in which the tail, 

 of the females at least, and most generally in both sexes, is composed 

 of seven complete joints or segments, we now pass to those in which 

 of more than six. The feet are usually long and 

 filiform, as in the last sub-genera. With the exception of the Lep- 

 topi, these Crustacea are almost removed from the preceding by the 

 of the third joint of the external foot-jaws. It is proportionally 

 mil-rower, and contracted at base, and the ensuing joint appears to 

 hi- inserted at the middle of its superior margin, or more externally. 

 The following sub-genus differs from those which succeed to it, in 

 the tail of the males, where we only find three segments. The form 

 of the third joint of the external foot-jaws appears to me the same as 

 in the preceding MI' 



* Cancer amnrwt, L.; Leach, Malac. Brit., XXI, A; Herbst., XVII. 69 ; 

 Hyat toarctata, Leach, Ib., xxi, H. 



t Libinia canalic*lata, AiM.I. Nat. Sc. Philud. vol. I, p. 77, iv, 1; 



L. fmarginata, Leach, Zool. Misc., cviii. 



I Doclaa Rissonnii, Leach, Zool. Misc. Ixxiv. The Inaehws oris and the T. 

 *f*n<ft, Fab., should be referred to it. 



* yertM4*ca, Leach, Zool. Misc., Ixiii; l*ach*s tpintfer, Fab. 



