he specimens which I
have examined, which were grouped in a bunch) taper at the lower end to
a point; and after careful examination, I feel sure that the cement does
not debouch from several successively formed orifices, as in _S.
vulgare_ and as in some Pollicipes, but only from the two original
orifices in the prehensile antennae of the larva. In these latter organs,
the sucking disc is hoof-like and pointed, and is narrower than the
basal segment. The ultimate segment has on its inner side (supposing
this segment stretched straight forwards,) a notch or step bearing at
least three spines. The proportions of the different parts differ
slightly from those in _S. vulgare_; but, as I shall hereafter have to
give all the measurements, I do not think them worth repeating here. In
the one large group of specimens examined by me, in Mr. Cuming's
possession, all were attached symmetrically to the coralline, as in the
case of _S. vulgare_, capitulum upwards, and their carinas outwards.

_Length_ of capitulum about three quarters of an inch; width about half
an inch; entire length, with peduncle, a little more than one inch.

The _Mouth_ is placed far from the adductor muscle.

_Labrum_, with its basal margin much produced; upper part highly
bullate, forming a rounded projection equalling the longitudinal axis of
the rest of the mouth; crest without any teeth.

_Palpi_, triangular, with the two margins, thickly clothed with
bristles; on each side of the mouth, near where the palpi are united to
the mandibles, there is a slight, orbicular, shield-like swelling.

The _Mandibles_ (Pl. X, fig. 3) have nine or ten very unequal teeth,
with the inferior angle rather broad and pectinated; of these, there are
four main teeth, of which the second is always the smallest, and between
the four, one or two small teeth are interpolated; so that the total
number is either nine or ten, and often varies on the two sides of the
same individual, as likewise does the shape of the inferior angle.

_Maxillae_, with the edge nearly half as long as that of the mandibles,
supporting from seventeen to twenty pairs of spines; the upper pair is
only slightly larger than the others; a part near the inferior angle
projects slightly beyond the rest of the nearly straight edge. The
apodeme, at its base or point of origin, is unusually broad and flat.

_Outer Maxillae_, large and triangular. The inner margin is slightly
concave, and continuously covered w