168 



PEDUNCULATA. 



provided with a mantle, having tentacular, cirrous, many- 

 jointed arms or feelers above. 



The class Cirripeda is divided by Lamarck into two 

 orders: — I. Pedunculata. The body supported by a 

 tubular moveable peduncle, the base of which is attached 

 to extraneous substances in the ocean, such as stones, wood, 



&c. ; the mouth is usually placed below II. Sessilia. 



The body without a peduncle, and attached to extraneous 

 substances; the mouth usually at the upper and anterior 

 part of the body. 



All the Cirripeda have their shells multivalve, or com- 

 posed of a number of pieces. 



ORDER I.-PEDUNCULATA. 



Body supported on a tubular fleshy peduncle. 



Genus 1.— OTION — Leach. 



Generic Character Body pedunculated, enveloped in a 



membranous tunic, which is ventricose above; two horn- 

 like tubes, directed backwards, truncated, open at theii 

 points, and situated in the apex of the tunic; having a lateral 

 opening, with many articulated and ciliated arms. Shell 

 consisting of two small testaceous semilunar valves, attached 

 near the lateral opening. 



Otion BlainvilUi Blainville's Otion. Plate XIX. 



fig. 1. Ash-coloured; the body and horns spotted with 

 black. Inhabits the North seas. 



Genus 2— CINERAS.— XeacA. 



Generic Character Body pedunculated, encased in a 



membranous tunic, which is swollen above, with an opening 

 below the summit, from which protrude many ciliated, ar- 

 ticulated arms. Shell having five testaceous, oblong, sepa- 



