CLASS THIRD. 



CIRRIPEDA. 



The animals are soft, destitute of a head, and consequently 

 of eyes ; covered with a shell, and are incapable of locomotion, 

 being always affixed to extraneous bodies. 



The whole of the Cirripedes are multivalve ; that is, consist- 

 ing of more than two pieces, or valves. 



ORDER I.— PEDUNCULATA. 



Body supported on a tubular, membranaceous, moveable pe- 

 duncle, the base of which is affixed to stones and other marine 

 bodies, or timber floating in the ocean. 



Genus 1 — Otion Leach. 



Body of the animal subquadrate, placed on a fleshy peduncle, 

 with an ovate, wide aperture, for the passage of the ciliated ten- 

 tacula, surmounted by two auriform processes ; shell concealed, 

 and composed of five widely separated, hidden valves; two 

 semilunate ones situate at the lower sides of the aperture, two 

 very small terminal, two very small ones placed on each side 

 of a small fissure at the top of the aperture, and a dorsal very 

 minute one. 



1. Otion Blainvillii, pi. LI, f. 13, 14, 15. 



Otion Blainvillii, First Ed., pi. 5, f. 13, 14, 15. 



Variety 1, f. 18. 



Otion Blainvillii, Leach, Ency. Brit. Sup., Art. Cirripedes, 

 pi. 57, f. 3; Lamarck, V, p. 510; Lepas Blainvillii, Brown, 

 Ency. Brit., VI, p. 404; lb., Conch. Text Book, p. 148, pi. 

 19, f. 1. 



Ventricose, membranaceous, seated on a tube, and sur- 

 mounted by two auriform appendages ; colour whitish, spotted 

 and streaked with brownish-purple. 



Found alive on a piece of rotten wood, on the south coast of 

 Devon. 



Variety 2, f. 14, 15. 



Lepas cornuta, Montagu, Linn. Trans., XI, p. 179, pi- 12, 

 f. 1. 



Found alive on the bottom of a transport, stranded on the 

 Devonshire coast. 



It is very doubtful whether shells of this genus have ever 

 bred in the British seas. 



Genus 2 — Cineras Leach. 



Animal with a quadrate body, seated on a fleshy peduncle, 

 covered with a membranaceous epidermis ; an aperture in front 

 for the passage of the ciliated tentacula ; immediately over this 

 are a pair of small elongated valves, placed nearly horizontal ; 

 two tripartite valves situate just below the aperture, one on 

 each side, and placed nearly perpendicularly, and an angulated, 

 keel-shaped, dorsal valve, but these do not cover the body. 



1. ClNERAS VITTATA, pi. LVI, f. 16, 18. 



Cineras vittata, var. a, First Ed., pi. 5, f. 16, 18; Leach, 

 Ency. Brit. Sup., pi. 57, f. 1 ; Lamarck, V, p. 408 ; Lepas vit- 

 tata, Brown, Ency. Brit., VI, p. 404 ; Lepas membranacea, 

 Montagu, Sup., p. 164; lb., Linn. Trans., XI, p. 182, pi. 12, 

 f. 2. 



Membranaceous, ventricose, truncated, and angular at the 

 summit ; olive-green with black stripes, and fine, minute, nar- 

 row, distant valves. 



Variety b, f. 17. 



Found on the coast of Wales, and has been met with on the 

 Forfarshire coast, near Montrose. 



2. Cineras aurita, pi. LI, f. 19. 



Cineras aurita, First Ed., pi. 1, f. 19; Lepas aurita, Brown, 

 Ency. Brit., VI, p. 404. 



Peduncle and whole external membrane greenish ash-colour- 

 ed, with three longitudinal lines of black ; two short, rounded, 

 auriform, blunted processes behind. 



Differs from the preceding species in being devoid of white 

 markings, and probably only a variety of that shell. 



Found at Plymouth. 



Genus 3 Pollicipes Leach. 



Body covered by a shell, and supported by a tubular, tendi- 

 nous, squamiferous peduncle, which seldom exceeds two inches 

 in length ; shell multivalve, compressed on the sides, with the 

 valves nearly contiguous and unequal ; valves thirteen or more 

 in number, those on the sides smallest ; five upper valves much 

 larger than the others; the anterior pair conical, elongated, with 

 their sides reflected backwards, situate on each side of the 

 opening; the central, or terminal pair largest, and trapeziform, 

 with an acute angle at the posterior extremity ; dorsal valve 

 greatly elongated, broad at the base, rounded in the back, with 

 an acute apex ; between these, in the peduncle, are a number 

 of smaller, testaceous, generally triangular studs. 



1. Pollicipes cornucopia, pi. LI, f. 11, 12. 



Pollicipes cornucopia, var. a, First Ed., pi. 5, f. 11, 12; 

 Lamarck, V, p. 406 ; Leach, Ency. Brit. Sup., Cirripedes, pi. 

 57; Brown, Ency. Brit., VI, p. 403; Lepas Pollicepes, Mon- 

 tagu, Sup., p. 6, pi. 28, f. 5. 



Valves smooth and glossy ; peduncle slightly compressed, 

 variable in length, and covered with numerous, small, glossy, 

 brown, shagreen-like scales, arranged in an imbricated manner, 

 and entirely covering the membranaceous skin. 



Variety b, f. 12. 



Found on drifted wood, in the Frith of Forth, and also on 

 the Irish coast. 



