206 
CLASS CRUSTACEA. 
dactylous forceps. Tlie appendages of the tail are six in 
number, and in the form of stylets, elongated, forked, or biden- 
ticulate at their extremity. Six vesicular sacs are visible 
between the final feet. It appears that there are many spe- 
cies, but they have not been described in a comparative and 
rigorous manner. The type is Cancer Sedeniarius, Forsk. 
In others the number of the antennae is four ; all the feet 
are simple. The tail has, at each side of its extremity, a 
lamellary or foliaceous fin, the lamina) of which are pointed 
or unidenticulate at the end. 
Hyperia, Latr., 
Whose body is thicker in front, whose head is occupied for 
the most part by oblong eyes, a little emarginated at the in- 
ternal edge, two of whose antennae are as long at least as one 
half the body, and terminated by a setaceous stem, long, and 
composed of many small articulations. ( Cancer monoculoides, 
Montague.) 
Phrosine, Risso. 
Similar, in the form of the body, and that of the head, to hype- 
ria, but the antennae are at most only of the length of this 
part, with but few articulations, in the form of stylet, or 
terminated by a stem, in an elongated cone. ( Phrosine ma- 
crophthalma, Risso.) 
Dactylocera, Latr., 
Whose body is not thickened in front, whose head is of middle 
size, depressed, almost squared, with the eyes small, and 
whose antennae, very short, and with few articulations, are of 
diverse forms ; the inferior being slender, and in the form of 
a stylet, the superior being terminated by a small lamina, 
concave at the internal side, and representing a sort of spoon 
or pincer. ( Phrosina Semilunata, Risso.) 
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