199 



3. Lingula. A subequivalved, flat, ovally oblong bi- 

 valve, truncated at its top ; rather pointed at its base ; 

 raised on a fleshy tendinous pedicle, and fixed to marine 

 bodies ; the hinge toothless. Recent and fossil. PL vi. 

 fig. 28. 



Cirrhipeda. Soft animals, without head or eyes, fixed 

 and testaceous. The shell either sessile, or raised on a 

 flexible tendinous pedicle. 



Sessile. Shell fixed generally on marine bodies ; the 

 mouth in the upper and anterior part. 



1. Tttbicinella. A straight cylindraceo-tubular opercu- 

 lated shell, attenuated towards its base, girt with transverse 

 annular ribs ; truncated at both ends, shut at the bottom by 

 a membrane, and open at the top. The operculum formed 

 of four small obtuse valves. Attached to the whale ; but 

 not known in a mineralized state. 



2. Coronula. A sessile, suborbicular, or subconical shell, 

 the extremities truncated; the sides thick; hollowed out 

 internally into radiating cells. The operculum formed by 

 four small obtuse valves. Recent, and very rarely fossil. 

 PL viii. fig. 27. The figure given here is of the fossil 

 coronula of the whale. 



3. Balanvs. A sessile, affixed, conical univalve, the 

 apex truncated ; the base closed by an adherent testaceous 

 plate ; the opening subtrigonal or elliptical ; the operculum 

 internal, with four moveable valves inserted near the inner 

 base of the shell. Recent and fossil. PL viii. fig. 26. 



4. Acasta. A sessile body, composed of separable 

 pieces, with a convex base, and a four-valved operculum. 

 Recent. 



5. Creusia. Sessile and subglobular, formed of four 

 valves, and having an internal bivalved operculum. Recent. 



6. Pyrgoma. Sessile, subglobular, with a bivalved oper- 

 culum : found on astrea, /nadrepora, &c. Recent. 



