376 
CLASS CRUSTACEA. 
enlarged thigh, terminated by a strong claw. The second and 
third segments are almost lunulated, and support, each, a pair 
of feet, formed of a single articulation, terminated by two sorts 
of digits, denticulated at the end. To the fourth segment is 
attached another pair of feet, the fifth and last, but in the form 
of simple, oval vesicles, divergent, and immoveable, and which 
Hermann presumes to be ovaries, rather than feet. Both this 
segment and the following are almost square ; the sixth is 
much longer and cylindrical ; the seventh and last is three 
times shorter, almost orbicular, flatted, and terminated by two 
small vesicles. The eyes are not distinct. 
Dichelestinm Sturionis , Hermann, fils, Mem. Apterol, 
page 125, v. 7, 8 ; Desmar. Consid., L. v,, is about seven 
lines in length, and one in breadth. The second segment, 
lengthened on each side into an obtuse papilla, and the follow- 
ing four are red, and of a whitish-yellow laterally. The feet 
do not appear when the animal is viewed from above. It 
insinuates itself deeply into the skin, and covers the osseous 
arches of the gills, but without fixing itself, as would appear, 
on their combs. Hermann has collected as many as a dozen 
from a single fish. Two or three of this number, males, per- 
haps, were one-third shorter than the others, and had a curved 
body ; one of these twelve individuals lived for three days. 
These Crustacea turn round frequently, and with vivacity; 
they hook themselves very strongly by means of their frontal 
forceps. 
Nicothoe, And. and Miln. Edw., 
Terminate the class of Crustacea, and are distinguished from 
the rest by their heteroclite form. They present, on a simple 
view, nothing but a body formed of two lobes, united in the 
manner of a horse-shoe, and enclosing two others. But when 
observed through the microscope, we discover that the two 
large lobes, are large lateral expansions of the thorax, in the 
