he has described under _L. nauta_, and which I cannot doubt is
the same with the present species, as the _L. anserifera_ of
Linnaeus; but I find it so named in all old collections, and it
seems to agree very well with Linnaeus's description. There has
been much groundless confusion about this species; I have no
hesitation in giving _A. striata_, of Brugiere, as a synonym,
though I have received from Paris the _Lepas pectinata_ of this
volume, named as the _A. striata_; and on the other hand, Poli
has incorrectly called a common variety of _L. pectinata_ by the
name of _L. anserifera_.

_L. valvis approximatis leviter sulcatis (tergis praecipue); scuto dextro
dente forti interno umbonali, laevo aut dente exiguo, aut mera crista
instructo; margine occludente arcuato, prominente: pedunculi parte
superiore aurantiaca._

Valves approximate, slightly furrowed, especially the terga; right-hand
scutum with a strong internal umbonal tooth; left-hand with a small
tooth, or mere ridge; occludent margin arched, protuberant: uppermost
part of peduncle orange-coloured.

Filaments five or six on each side.

Var. (_dilatata_, young); valves rather thin, finely furrowed, often
strongly pectinated; scuta broad, with the occludent margins much
arched, making the space wide between this margin and the ridge
connecting the umbo and the apex: carina often barbed.

Common on ships' bottoms from the Mediterranean, West Indies,
South America, Mauritius, Coast of Africa and the East-Indian
Archipelago. Central Pacific Ocean. China Sea. Chusan. Sydney.
Attached to pumice, various species of fuci, Janthinae, Spirulae;
often associated with _L. anatifera_ and _L. Hillii_, and, in a
young state, with _L. fascicularis_.

_General Appearance._--Capitulum more or less elongated relatively to
its breadth; in two specimens, with scuta of equal width, one was longer
than the other by the whole of the occludent margin of the terga. Valves
white, thick, (in young specimens sometimes diaphanous and thin,)
closely approximate to each other; surfaces furrowed to a very variable
amount. Terga generally more plainly furrowed than the scuta, of which
the basal portion is generally less furrowed than the upper part;
ridges, often rough, generally much narrower than the furrows: in
half-grown specimens (var., _dilatata_ of Leach,) the ridges are
frequently denticulated, and there is even sometimes a row o