Three other species—A. wawa° A. col-mate, and A. tubulose—are described by Darwin.
A nelasma, Darwin ; Alepas, Loven.—Capitulum without valves, aperture large, peduncle Ilmbri ated, sub-globular imbedded.
A. equaticola, Darwin, is the only species of this genus. It was referred by Loven to A tepee, but has been separated by Darwin. It lives parasitic, with its peduncle imbedded in the skin of sharks in the North Sea.
Alcippe, A. Hancock, 1849.—Capitulum without valves, with the aperture spinose; peduncle grows at its lower and, rostral surface depressed and covered by a horny' disc; capitulum and peduncle imbedded in a self-formed cavity.
This most remarkable genus bores cavities for itself in shells. It inhabits the shores of England. It has but one species, A. lampas, Hancock.
I blo,, Leach (Anatifa, Cuvier ; Tetralasmia, Cuvier).—Female and hermaphrodite with 4 horny valves ; peduncle clothed with persistent horny spines.
There are two species of this, I. Cumingii and I. quadrivalvis. This is one of the genera in which complemental males occur, the structure of which Mr. Darwin has described at great length.
I. Cumingii inhabits the seas of the Philippine Archipelago, and they are invariably attached to the peduncle of Pollicipes mitclla in groups of two or three together. I. guadrirelvis is fouud in the Australian seas.
Scalpellum, Leach (Lepas, Linn. ; Pollicipes, Lamarck ; Polylepas, De Blainville; Smilium, Leach ; Calantica, J. E. Gray; Thaliella, J. E. Gray ; Anatifa, Quoy and Gaimard ; Xiphidium, Dixon).— Hermaphrodite and female with valves 12 to 15 in number ; latera of the lower whorl 4 or 6, with their lines of growth generally directed towards each other; ,sub-rostrum very rarely present; peduncle squamiferous, most rarely naked.
S. vulgare, Leach. It is the Lepas Scalpellum, Linumus; Pollicipes Scalpellum, Lamarck ; Polylepaa vulgare, De Blainville ; Scalpellum lave, Leach. Hermaphrodite with capitulum of 14 valves, including Like the last, this species is extremely common on ships' bottoms from all parts of the world. It also attaches itself to sea-weed, turtles, and other objects.
the rudimentary rostrum; upper latent irregularly oval. Thu com plemental male flask-formed, with four rudimentary valets.
It is a native of the seas of Great Britain, Ireland, Prance, Norway, and Naplea. Found attached to horny corallines, according to Forbes and MaeAndrew, at from twenty to thirty, sometimes even to fifty fathoms in depth. There are five other species of this genus They
are all characterised by the presence of the complemental male.
l'ollicipes, Leach (Lepas, Linnteus ; Anal 'fa, Bruguibros ; Oken ; Ramphidionia, Schumacher ; I'utylepas, Do Blainville; Capitulani, J. E. Gray).—Valves from 18 to above 100 in number; latera of the lower whorl numerous, with their lines of growth directed downwards ; subrostrum always present; peduncle squami fermis.
I'. snitdla, Sowerby. It is Lepas Linnmus ; Polylepas initella, De Blain. ; Capit slain initella, Gray. Capitulum with only one whorl of valves under the rostrum ; the upper pair of latera viewed internally are three or four times as large as the lower laten, which overlap each other laterally ; scales of the peduncle symmetrically arranged in close whorls.
This species is found in the seas of the Philippine Archipelago and the Chinese Sea. There are five other species. They are found attached to both fixed 'and floating objects in the warmer, temperate, and tropical seas.
Lithotrya, G. B. Sowerby (Litholepas, De Blainville ; AU-La, Leach ; Bei:nails and Conchot rya, J. E. Gray ; Lepas, Gmclin ; A natifa, Quoy and Gaimard).—Valves 8, including a small often rudimentary ros trum and a pair of small lateen; lines of growth finely crenated ; peduncle covered with small calcareous scales; those of the upper whorls crenated ; attached either to a basal calcareous cup or to a row of discs.
Mr. G. B. Sowerby, who instituted the genus, considers it as inter mediate between the Sessile and Pedunculated Cirripedes ; and states that it possesses a peculiarity not to be found in any hitherto described genus of this class, namely, that of penetrating stones for its habitation. Rang says that De Blainville is of opinion that the genus is only a true Anaufa, which had affixed itself upon the valve of a Venerupis at the bottom of one of the cavities which that bivalve hollows out for itself. De Blainville, in his `Malacologie; describes it under the name of Lit hulepas, sinking Sowerby's name altogether, though he says the genus was newly established by him, quotes his description, and merely states that he has never seen the Cirripede.