hout the equatorial, temperate,
and cold seas; attached to floating objects, living or
inorganic.

The _Capitulum_ is formed of smooth membrane, including five small
valves, of which the terga and carina are often quite rudimentary or
absent. Valves minute, thin, generally more or less linear, placed far
distant from each other; sometimes imperfectly calcified and covered by
chitine membrane, or imbedded in it. The umbones of the valves
(together with the primordial valves) are nearly central, so that they
are added to at their upper and lower ends; hence their manner of growth
is considerably different from that of the valves in Lepas. The adductor
muscle is attached to a slight concavity on the under side of each
scutum, at the point whence the lobes diverge.

The _Terga_ are placed almost transversely to the scuta; at their lower
ends, there is either a very slight prominence in the capitulum, or
there is a large tubular, folded appendage, opening into the sack, and
apparently serving for respiratory purposes.

_Peduncle_, smooth, moderately long; attachment effected by the
cement-stuff being poured out exclusively, as it appears, from the
larval antennae. These antennae in _C. aurita_ and _C. virgata_, resemble,
in the form of the disc and in the long feathered spines on the ultimate
segment, those in Lepas.

The _Filamentary Appendages_ are highly developed; there are six or
seven on each side; two are attached beneath the basal articulation of
the first cirrus (as is usual in Lepas), and near them there are one or
two small pap-formed projections of apparently similar nature; the rest
of the filaments are attached to the posterior edges low down, on the
lower segments of the pedicels of the cirri. I believe, in all cases,
these appendages are occupied by testes.

_Prosoma_, moderately developed.

_Mouth_, situated not far from the adductor muscle; labrum considerably
bullate, with the crest hairy and pectinated with inwardly pointing,
approximate, flattened teeth: inner fold of the supra-oesophageal cavity
slightly thickened and yellowish, villose on the sides.

_Palpi_ of the usual shape, not meeting, moderately broad.

_Mandibles_, with five teeth, graduated in size, nearly equidistant,
finely pectinated either on one or both sides towards their bases;
inferior angle narrow, either produced into a fine tooth, or almost
rudimentary.

_Maxillae_, about 3/4ths of the size of the mandibles, step-f