526 
pair of antennae ; and on the ventral aspect a pair of hook organs 
and three pairs of foot-jaws. The antennae were segmented, the 
terminal segments being provided with hairs. Each hook organ 
consisted of a basal segment and a terminal hook ; the former of 
which was supported on a well-marked triangular frame, on which 
it was moved by the action of powerful muscles. The foot jaws, 
attached a little on one side of the mesial line, consisted of three 
pairs. The first and second foot-jaws consisted each of two seg- 
ments. The terminal segment in the first foot-jaw was formed of 
two chitinic plates, connected by their anterior margins, but sepa- 
rated at their posterior margins, which were armed with teeth. The 
corresponding segment in the second foot-jaw consisted of but a 
single plate, toothed along its posterior margin. The third foot- 
jaw had three segments, the terminal one being destitute of teeth. 
The cephalic was separated from the thoracic part by a constricted 
neck. 
The thoracic part was characterised by its processes, seven dorsal, 
two ventral, and five lateral, the cavities within which communi- 
cated with the general cavity of the thorax. Its division into 
four segments was indicated by constrictions. The first and second 
segments bore each a pair of feet on their ventral aspects. 
The abdominal part, very small, was divided into two segments, 
the anterior of which presented a pair of nipple-like projections, to 
one of which the male was attached. Of these the authors gave a 
minute description. Two genital orifices opened, one on each side 
of this segment. From each orifice a, long string of ova, spirally 
twisted, depended. The ovaries consisted of a branched system of 
tubes, occupying the cavity of the thorax, and extending into the 
processes and feet. Each ovary communicated close to the genital 
orifice with the cement organ. The alimentary canal, axially situ- 
ated, commenced at the oral aperture, which was situated immedi- 
ately in front of the first pair of foot-jaws. It reached almost 
as far as the thoracic end of the animal. It possessed lateral dilata- 
tions, but no anus. 
Male, very minute, ^th of an inch in length, pyriform in shape. 
Divided into cephalic, thoracic, and abdominal parts — cephalic end 
broadest and largest ; furnished with antennse, hook organs, and foot- 
jaws. By its hook organs it was attached to one of the nipple-like 
projections on the body of the female, on which it was parasitic. 
