of reproduction, for
there were only two or three ova attached to the fraenum on one side, and
not very many on the other. The ova are much less elongated than is
usual; they are of a remarkable size, namely 22/1000ths of an inch in
their longer diameter; the membrane by which they are united into a pair
of lamellae is remarkably strong; the fraenum (Pl. IV, fig. 2 _f_) on each
side is large, strong, with rounded edges, pale coloured and hence
conspicuous; on the side nearest the body, the whole surface is covered
with club-shaped glands, having very short footstalks, and being in
total length 5/6000ths of an inch; these glands secrete a reticulated
layer of gut-formed fibres, attached to the ovigerous lamellae. In the
specimen described by Loven, the lamellae (fig. 1, and fig. 2, _b_, _b_)
appear to have been very large: and in that examined by myself, the
peduncle was gorged with immature ova, showing that the female
reproductive powers were ample, though at the foregoing period, only a
few eggs had been formed.

_Habits._--According to Loven, this species lives imbedded in the skin
of _Squalus maximus_ and _spinax_, in the North Sea: I suspect that it
is not closely compressed in its cavity, otherwise, I do not see the use
of the two layers of muscles round the whole peduncle; it probably
adheres to the sides of the cavity by the tips of the branched,
root-like filaments; owing to the flexible nature of the capitulum, this
Cirripede can offer little resistance to the water, and, therefore, is
little likely to be torn out of its cavity. I have no doubt that it can
fold the membrane of the capitulum, like a cloak, round its thorax and
cirri; but it certainly can offer far less resistance, than other
Cirripedes, to any enemy. This creature must obtain its food, and
considering its productiveness much food must be required, in a manner
quite different from nearly every other member of its Order. As the
whole of the peduncle is imbedded, and as the mouth is probosciformed,
with the labrum a little curled over the adductor muscle, I conclude
that this Cirripede can reach minute animals crawling by on the surface
of the shark's body.

It must be borne in mind that the mouth, as in all Cirripedes, has the
power of independent movement, and that the mandibles and maxillae are
here beautifully adapted to catch and force down any small living
creature into the muscular oesophagus; the rudimentary outer maxillae,
moreover, no