226 OTULITM. 



OTIDES. Bl. The first order of Scutibranchiata, BL containing 

 the genera Haliotis and Ancylus. 



OTION. Leach, (wnov, a little ear.) Included by Darwin in 

 his work on Cirripedes, with Cikeras, under the name CoN- 

 CHODERMA defers. Order. Pedunculated Cirripedes, Lam. — 

 Descr. Body sub-quadrate, supported on a fleshy pedicle with a 

 gaping aperture and two posterior auricular tubes ; valves five, 

 separate, two semilunar, placed at the sides of the aperture, two 

 terminal, very small, one dorsal, minute. — Obs. Otion differs 

 from Cineras in having two cylindrical posterior tubes, and in 

 the extreme minuteness of three out of five of the valves. Eound 

 on spars floating in the sea, &c. (Lepas aurita, Linn.) O. 

 Cuvieri. PI. ii, fig. 43. 



OTIS. Humph. Aueictjla, Lam. 



OVATE. (Ovatus.) Egg-shaped or oval. 



OVEOLITHES. Montf. A microscopic shell resembling Bullae 



OVIPAEOUS MOLLUSCA. Those which produce their young 

 in eggs. Used in distinction from the Viviparous Mollitsca, 

 whose young are perfectly formed before they leave the body of 

 the parent. 



OUTEE LIP. See Labrtjm. 



OVIJLUM. Brug. {Ovum, an egg, dim.) Fam. Convoluta, 

 Lam. Angyostomata, Bl. — Descr. Ovate or fusiform, smooth, 

 convolute, spire covered ; aperture narrow, with a canal at each 

 extremity ; outer lip crenulated, inflected ; inner lip smooth, 

 callous towards the spiral extremity ; dorsal area wide, some- 

 times indistinctly marked. — Obs. The Ovula were placed by 

 Linnaeus in his genus Bulla, from which they are very remote. 

 They differ from Cyprsea in having the inner lip smooth. "We 

 have given representations of their different forms as follows : 

 O. Ovum, fig. 442. O. verrucosum, (Calpurnus Montf.) fig. 



.441. O. Volva, the weaver's shuttle (Eadius, Montf.) fig. 422. 

 O. gibbosum, (Ultimus, Montf.) fig. 443. The Monograph in 

 the Thesaurus Conchyliorum, PI. 9, enumerates forty-eight 

 ■species of this beautiful genus of shells. See our Plate xx. fig. 

 441 to 443. 



