188 
CRUSTACEA, 
in both sexes ; the shell ovoid, widely truncated, without any projec- 
tion like a rostrum, and flattftied. 
As remarked by Desmarest, we may observe on ('ach side and 
above the origin of the claws, an oblique fissure resembling a button- 
hole, longitudinally intersected by a diaphragm, ciliated, like itself, 
on the margin that communicates with the branchiae, and affording 
an issue to the water that bathes them. 
Three species are found in the Mediterranean* ; the others 
inhabit Oriental seas, and one of them D. quadriclens, Fabr., 
IJerbst., X, 70, is also obtained there in a fossil state. 
There, the shell is sometimes nearly orbicular, or globular, and 
sometimes arcuated anteriorly and narrowed posteriorly, and dentated 
or spinous on the sides. The eyes are situated near the middle of the 
front, and placed on short pedicles. 
Dromia, Fab. 
The four posterior feet inserted in the back, and terminated by a 
double hook ; the shell suborbievdar or nearly globular, convex and 
Avoolly, or very hairy. 
Whlh their hind feet they seize upon Alcyonii, shells, and other 
bodies, beneath which they shelter themselves, transporting them 
wherever they go. 
The most common species, — Cancer dorniia, L. Rumph., 
Mus., XI, 1 ; Herbst., XVII 1, 103, is found in every sea, tliat of 
the North excepted. It is covered with a brown down, and has 
five teeth on each lateral margin and thi’ee in front. The fingers 
are stout, deeply dentated on the two edges, and partly rose- 
coloured. Some authors say that it is venomous. 
The Death’s Head, — Cancer caput mortuurn, L. ; Donnin. 
ch/peata. Act. Hafn., 1802, is smaller, more convex, almost 
globular, with three teetli on each side in its anterior margin, 
and has a short front, emarginate in the middle and laterally 
sinuous. It is found on the coast of Barbary f. 
Dynomenk, Lat. 
The two posterior feet much smaller than the others, alone dorsal, 
and ajiparently unarmed ; the shell widened, and nearly resembling 
a reversed heart truncated i)Osteriorly, like that of the last Quadri- 
latera, and siinplv pubescent. The ocular pedicles are longer tlian 
those of the Dromiae. 
But a single species, tlie Dynomene Id'^pide, Desmar., t'onsid., 
XVIII, 2, is known ; it is found at the Isle of France, 
The last Notopoda difl’er from the preceding in the feet, all of 
whicli except the claws, terminate in a fin, and from all the Brachy- 
nra in the extension of tlieir tail. iSuch is the 
* Durippe lanata ; Cancer lanalv.s, L. ; Desmar., Consider., XYII, 2 ; — />. 
ptfinis, Id.; Ilerbst., XI, 67; — Cancer muscarone, Herbst., XI, 68. 
•(' For the other species see Desmar,, Comid. Gen, siir la Classc dcs Critsl., 
p. 186, et seq. 
