ith 14 reddish valves: carina with the roof
flat, bordered on each side by a rounded ridge; basal margin truncated:
upper latera twice as long as broad.

Mandibles with three teeth: maxillae narrow, bearing only four or five
pair of spines: segments of the second and third pair of cirri with one
side wholly covered with spines.

MALES, two, lodged in hollows, on the under sides of the scuta;
pouch-formed, with four (?) rudimentary valves; no mouth; cirri not
prehensile.

Hab. unknown; associated with _Dichelaspis orthogonia_. British
Museum.

FEMALE OR HERMAPHRODITE.

There is only a single specimen in the British Museum, and this had
nearly all its valves separated, and many of them in fragments: from its
state of decay, I think the specimen must have been dead, when
originally collected.

_Description._--The capitulum consists of fourteen valves, including
from analogy a rostrum.[58] Valves, apparently covered with membrane,
bearing some thin spines on the margins; clouded with a fine, though
pale, orange tint; surfaces plainly marked with lines of growth.

[58] In my first, and as I thought careful examination of the
separated valves (my only materials) of this species, I mistook
one of the triangular rostral latera for the rostrum, and hence
was unfortunately led into an error in my 'Monograph on the
Fossil Lepadidae of Great Britain,' in which I state that the
present species has only twelve valves in the capitulum; and I
inferred from this, that _S. quadratum_, _S. fossula_, &c., had
only twelve valves; I still believe this to be correct, but the
existence of fourteen valves in _S. rutilum_ and _S. ornatum_,
the recent species to which the above fossils are most closely
allied, no doubt is a strong argument in favour of this higher
number.

_Scuta_, elongated, nearly three times as long as broad; apex, pointed;
basal margin extremely oblique, forming an acute angle with the
occludent margin; the lateral margin is slightly hollowed out, and is
separated from the tergal margin by a large rectangular projection or
shoulder. The occludent margin is nearly straight; externally, there is
a slight ridge running down the middle of the valve, from the apex to
the baso-lateral angle; and a second ridge running from the apex to the
tergo-lateral angle. The lines of growth do not end abruptly at the
tergo-lateral angle, as is the case with _S. ornatum_ and several fossi