an the
homologies of the different parts be clearly understood.

_On the Names given to the different parts of Cirripedes._

I have unwillingly found it indispensable to give names to several
valves, and to some few of the softer parts of Cirripedes. The
accompanying figure of an imaginary Scalpellum includes every valve; the
two most important valves of Lepas are also given, in which the
direction of the lines of growth and general shape differ from those of
Scalpellum as much as they do in any genus. The names which I have
imposed will, I hope, be thus acquired without much difficulty.

Whoever will refer to the published descriptions of recent and fossil
Cirripedia, will find the utmost confusion in the existing nomenclature:
thus, the valve named in the woodcut the _Scutum_, has been designated
by various well-known naturalists as the "ventral," the "anterior," the
"inferior," the "ante-lateral," and the "latero-inferior" valve; the
first two of these titles have, moreover, been applied to the rostrum or
rostral valve of sessile Cirripedes. The _Tergum_ has been called the
"dorsal," the "posterior," the "superior," the "central," the
"terminal," the "postero-lateral," and the "latero-superior" valve. The
_Carina_ has received the first two of these identical epithets, viz.
the "dorsal" and the "posterior;" and likewise has been called the
"keel-valve." The confusion, however, becomes far worse, when any
individual valve is described, for the very same margin which is
anterior or inferior in the eyes of one author, is the posterior or
superior in those of another; it has often happened to me that I have
been quite unable even to conjecture to which margin or part of a valve
an author was referring. Moreover, the length of these double titles is
inconvenient. Hence, as I have to describe all the recent and fossil
species, I trust I may be thought justified in giving short names to
each of the more important valves, these being common to the
pedunculated and sessile Cirripedes.

The part supported by the peduncle, and which is generally, though not
always, protected by valves, I have designated the _Capitulum_.

The title of _Peduncle_, which is either naked or squamiferous, requires
no explanation; the scales on it, and the lower valves of the capitulum,
are arranged in whorls, which, in the Latin specific descriptions, I
have called by the botanical term of verticillus.

I have applied the term _Scutum_ to th