30 CONCHOLOGY. 



CLASS IL 



CIRRHIPEDA. 



Animal, yoft, without head or eyes, testaceous, body fixed as 

 if reversed, inarticulated, furnished with a mantle, having above 

 tentacular arms, with curled tufts multiarticulated, mouth beneath, 

 not projecting, dentated transverse jaws disposed in pairs. 

 Number of arras, unequal and varying, disposed in rows, each 

 composed of two rows of curled tufts of bristles ; fringed ; a cor- 

 neous skin supported by a pedicle. Medulla longitudinal and 

 knotted ; gills external, sometimes concealed ; circulation by heart 

 and vessels. One Family. 



FAMILY. 



CiRRHiPEDA. Ten Genera. 

 1. Genus Tubicinella. PI. V. 

 Animal. Body inclosed in a shell, with small setaceous and 

 unnequal cirri. 



Shell. Univalve, operculated, tubular, erect, a little attenuated 

 towards the base, bound with annular transvere ribs, truncated 

 at both ends, open at the summit, and closed at the base with a 

 membrane. Operculum with four obtuse valves. South American 

 seas. One species. 



Tubicinella valanarum. 



2. Genus Coronula. PI. V. 

 Animal. Body seated, enveloped in a shell with small setaceous 

 and cirrous arms. 



Shell. Sessile, apparently indivisible, suborbicular, conoidal 

 or blunt, conical, the extremities truncated, the sides very thick, 

 the inside hollowed into radiating cells. Operculum composed of 

 four obtuse valves. Inhabits the north seas. Four species. 

 Coronula diadema. Coronula valaenaris. 



C. testudinaria. C. pulchra. 



