The peduncle is short, yellow, and tuberculated. The general appearance of the drawing makes me suspect that it is a Paecilasma.
CLYPTRA. _Leach._ Zoological Journal, vol. ii, p. 208, July, 1825.
Leach has most briefly characterised a specimen in Savigny"s Museum, from the Red Sea, under the above name of _Clyptra_. It has only four valves, and its peduncle is smooth; by the latter character it is distinguished from Ibla. Apparently this is a distinct and new genus.
Mr. J. E. Gray, in "Proc. Zoolog. Soc.," 1848, p. 44, quotes a description by Stroem ("Nym. Saml. Danske," 1788, 295, n. iii, f. 20), namely, "_Lepas testa compressa 7-valvis, stipite lamellosa_." It is found attached to _Gorgonia placomus_, in the North Sea. I suspect that this is the common _Scalpellum vulgare_, and that Stroem counted the valves only on one side, overlooking the rudimentary and concealed rostrum; and this would give seven for the number of the valves. Had it not been for the expression "stipite lamellosa," I should have thought this might have been an unknown species of Dichelaspis.
SCALPELLUM LaeVIS. _Risso._ Hist. Nat. des Product. de l"Europe Merid., 1826, Tom. iv, p. 385.
The chief characteristic of this species appears to be indicated by its specific name. It is found in the Mediterranean, attached to Cidarites.
I am inclined to believe that it is distinct from _S. vulgare_.
SCALPELLUM PAPILLOSUM. _King._ Zoolog. Journal, vol. v, p. 334.
Captain King has described this species, taken from the depth of 48 fathoms, on the coast of Patagonia, in Lat. 44 30" S. It is probably distinct, but is so imperfectly described, that not even the number of the valves is given.
POLYLEPAS (POLLICIPES), Sinensis. _Chenu._ Ill.u.s.t. Conchyliolog., Pl. II, fig. 7.
This species is said to come from China; it is nearest to _P. spinosus_, but is, I think, distinct.
EXPLANATION OF THE PLATES.
TAB. I.
Fig.
1. _Lepas anatifera_, (nat. size.) _Var._, with a row of square, dark-coloured marks on the scuta and terga.
1_a._ _Lepas anatifera_, external view of carina, magnified thrice.
1_b._ _Lepas anatifera_, lateral view of carina, magnified thrice; var. _dentata_.
1_c._ _Lepas anatifera_, internal view of right-hand scutum, to show the tooth at the umbo.
2. _Lepas Hillii_, (nat. size.)
3. _Lepas pectinata_, (magnified thrice.)
3_a._ _Lepas pectinata_, var. (_spirulae_), tergum, magnified thrice.
4. _Lepas anserifera_, (nat. size.)
5. _Lepas australis_, (nat. size.)
5_a._ _Lepas australis_, carina, external view of, magnified twice.
6. _Lepas fascicularis_, (nat. size,) with its peduncle, together with those of three other specimens, imbedded in a vesicular ball of their own formation, of which a slice has been cut off to show the internal structure. The specimen is in the College of Surgeons.
6_a._ _Lepas fascicularis_, carina of, nat. size.
6_b._ _Lepas fascicularis_, var. _villosa_.
6_c._ _Lepas fascicularis_, var. _villosa_, carina of.
6_d._ Part of the membrane from one side of the peduncle of _Lepas fascicularis_, with the ball removed, showing one of the cement-ducts, and the orifices through which the vesicular membrane forming the ball has been secreted; greatly magnified; viewed from the outside.
TAB. II.
Fig.
1. _Poecilisma Kaempferi_, (magnified two and a half times.)
1_a._ _Poecilisma Kaempferi_, carina of.
2. _Poecilisma aurantia_, (magnified two and a half times.)
3. _Poecilisma cra.s.sa_, (magnified twice.)
3_a._ _Poecilisma cra.s.sa_, carina of.
4. _Poecilasma fissa_, (magnified five times.)
5. _Poecilasma eburnea_, (magnified five times.)
5_a._ _Poecilasma eburnea_, carina of, external view of.
5_c._ _Poecilasma eburnea_, carina of, lateral view of.
5_b._ _Poecilasma eburnea_, scutum, internal view of.
6. _Dichelaspis Warwickii_, (magnified five times.)
6_a._ _Dichelaspis Warwickii_, transverse section of the top of the peduncle, showing the deeply-notched end of the inwardly bent carina; magnified five times.
6_b._ _Dichelaspis Warwickii_, _var._, scutum and tergum.
7. _Dichelaspis pellucida_, (magnified five times.)