DECAPODA. 
187 
The others, such as the C. voide — Cancer calappa, L. ; Ca- 
lappa fornicata. Fab.; Herbst., XII, 73, 74, have the marginal 
dilatations of the shell entire. This species inhabits the seas in the 
vicinity of Australia and the Moluccas. 
^Ethra, Leach. 
The ^thrse differ from the Calappae in their very flat shell, in their 
forceps, which are not raised perpendicularly, and which do not 
overshadow the forepart of their body, and in the almost square form 
of the third joint of the external foot-jaws. 
Sometimes* the shell is a transversal oval, and at othersf forms 
a short and very wide triangle laterally dilated and rounded. The 
claws are but slightly elongated, and are tolerably thick; here they 
are longer, angular, and remind \is, as does also the form of the shell, 
of the Parthenopes. These latter species luight constitute a sej)arate 
subgenus. 
Finally, our last aud seventh division, that of the Notopoda, con- 
sists of Brachyura, whose last four or two feet are inserted above 
the level of the others, or which appear to be dorsal and look upwards. 
In those where they terminate by a sharp hook, they are usually 
employed by the animal in seizing various bodies, such as shells, 
Alcyonii, &c., with Avhich it covers itself. The tail consists of seven 
segments in both sexes. 
The tail of some of them, as in other Brachyura, is folded under, 
and their feet terminate in a sharp hook and are not fitted for 
natation. 
Here the shell is nearly square, and terminates anteriorly in an 
advancing and dentated point, or it is sidj-ovoid or truncated before. 
In the 
Homola, Leach, 
'I’he eyes are supported by long pedicles closely approximated at 
the base, and inserted under the middle of the front. The two posterior 
feet are alone turned up. The claws are larger in the males than in 
the females. 
The shell is extremely spinous, with a dentated projection on the 
middle of the front. The superior foot-jaws are elongated and 
salient. 
These Crustacea inhabit the Mediterranean, and were designated 
by Aldrovandus under the name of Hippocarcini ; they are the Thel- 
xiopes of Rafinesque. Some of the species attain a great size 
Dorippe, Fab. 
The eyes widely separated and placed at the anterior and lateral 
angles of the shell ; the four posterior feet turned uj) ; the claws short 
* Aithra depressa, Lam., Hist, lies Aiiim. sans Verteb. ; Cancer scniposiis, L. ; 
Cancer polynome, Ilerbst., liii, 4, 5; Desmar., Consid., X, 2. 
•f- Parthenope, fornicata, Fab. 
t Homola sjrinifrons, Leach, Zool. Misc., Ixxxviii ; Cancer spinifrons, Fab. See 
the article Homole, Nouv. Diet, d’llist. Nat. Ed. II, and Desmar., Considth-., 
XVIII, 1. The Lorippe Cuvieri, Risso, belongs to this subgenus. 
