DECAPODA. 
183 
pedicles are susceptible of being entirely retracted within their fos- 
sulge, and are protected posteriorly by a dentiform projection, or 
angle, of the lateral edges of the shell. The second joint of the pe- 
duncle of the lateral antennae is much larger than the following one ; 
they are terminated by a very short stem resembling an elongated 
stylet. 
Hyas, Leach. 
Lateral edges of the shell dilated behind the ocular cavities, which 
are large and oA'al ; 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 fossulae are very small and nearly orbicular, and the 
ocular pedicles are A'ery short, and but very slightly exertile. The 
second joint of the lateral antennae is cylindrical, and not compressed, 
or but very slightly so. The body is nearly globular, or triangular. 
We Avill unite the Doclcea and the Egeria of Leach to his Li- 
BINI/E. 
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 tAvice that of the shell. 
The claAvs of the male Doclaea X are much shorter than the tAvo 
folloAving feet. The length of the latter is hardly more than once 
and a half that of the shell, Avhich is nearly globular and ahvays co- 
A’’ered Avith a broAvn or blackish doAvn. 
In the Egeriae § the claAVS are filiform, and the hands much elon- 
gated and almost linear. The folloAving feet are five or six times 
longer than the shell. The body is triangular. 
Having revieAved all the sub-genera of this tribe in Avhich the feet 
subsequent to the claAVS are of a similar form, and in Avhich the tail, 
of the females at least, and most genei’ally in both sexes, is composed 
of seA^en complete joints or segments, Ave noAV pass to those in Avhich 
it never consists 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 remoA'-ed from the preceding by the 
form of the third joint of the external foot-jaAVs. It is proportionally 
narroAver, and contracted at base, and the ensuing joint appears to 
be inserted at the middle of its superior margin, or more externally. 
The folloAving sub-genus differs from those Avhich succeed to it, in 
the tail of the males, Avhere Ave only find three segments. The form 
of the third joint of the external foot-jaAVS appears to me the same as 
in the ])receding sub-genera. 
* Cancer araneus, L. ; Leacli, Malac. 13rit., XXI, A; Herb.st., XVII. 59; — 
Hyas coarcfaia, Leach, Ib., x.\i, B. 
h Libinia canaliculaf a, Say, Jonrn. Acatl. Nat. Sc. Philad. vol. I, p. 77, iv, 1; 
I — C. emarfjinuta , Leach, Zool. Misc., cviii. 
:j; Doclcea Rissonnii, Leach, Zool. Misc. l.xxiv. The Inachus oris and the T. 
hybridus, Fab., should be referred to it. 
§ Eyeria indica, heach, Zool. Misc., l.\iii; Inachus spini/er, Fab. 
