PiECILOPODA. 
271 
two multifid feet ? — on each side placed on an eminence ; 4, four pre- 
hensile feet, the two first of which consist of a thigh and leg termi- 
nated by various unequal and dentated hooks, and the others of 
an enlarged thigh terminated by a small but stout nail. The second 
and third segments are almost lunulated, each bearing a pair of feet 
formed of a single joint, terminated by two kinds of toes, dentated at 
the end. To the fourth segment is attached another pair of feet, the 
fifth and last, but having the form of simple, oval, divergent, and 
immoveable vesicles, which Hermann presumes are rather ovaries than 
feet. This segment, as well as the next, is nearly square. The sixth 
is much longer, and cylindrical. The seventh and last is three times 
shorter, almost orbicular, flattened, and terminated by two small 
vesicles. The eyes are not distinct. 
Dichelestium sturionis, Herm., Jun. Mem. Apter. p. 125, V, 
7, 8 ; Desmar., Consid. L, v. About seven lines long and one 
broad. The second segment is prolonged on each side into an 
obtuse papilla, and the four following are red in the middle, 
with whitish-yellow along the lateral margins. When viewed 
from above, the feet are not visible. This animal penetrates 
deeply into the skin and places itself on the osseous arches of 
the branchiae, but without, as it appears, intruding upon their 
combs. Twelve of them were taken by Hermann from a single 
fish. Of this number, two or three, perhaps males, were one 
third shorter than the others, and had a curved body ; one of 
the twelve lived three dayfe. They are constantly whirling about 
and with considerable vivacity. By means of their frontal 
claws they are enabled to cling with great tenacity. 
Nicothoe, Aud. and Edw. 
These animals terminate the Crustacea, and are distinguished from 
all others of that class by their heteroclitical form. To the naked 
eye they seem nothing more than two lobes united in the form of a 
horse-shoe, which inclose two others. By the aid of glasses, how- 
ever, we discover that the two large lobes are formed by the great 
expansion of the sides of the thorax, which resemble wings, are 
almost oval and thrown behind ; that the two others are external 
ovaries or clusters of eggs, analogous to those of a female Cyclops, 
and inserted, one on each side, into the base of the abdomen by 
means of a short pedicle ; and that the body of the animal is com- 
posed of the following parts : 1 , a distinct head furnished with two 
separate eyes ; two short, setaceous, lateral antennse formed of eleven 
joints, each with a hair on the inner side ; a mouth forming a circular 
aperture Avhich acts as a cup, and accompanied on each side with — 
anterior feet — maxilliform appendages : 2, a thorax of four seg- 
ments, with five pairs of feet beneath, the two anterior of which 
are terminated by a stout hook, and are bidentated on the inner side ; 
the remaining eight being formed of one large joint, terminated by 
two nearly equal and cylindrical stems, each composed of three joints, 
and furnished with setae : 3, a pointed abdomen of five annulli, the 
first and largest of which gives origin to the oviferous sacs ; the last 
