10 CLASS ANNELIDA. 



side of its mouth is a plume of gills in the form of a fan, usually 

 tinted with lively colours. At the base of each plume is a fleshy 

 filament, one of which, either on the right side, or the left, 

 indifferently, is always elongated, or dilated at its extremity, 

 into a disc, variously configurated, which serves as an oper- 

 culum, and closes the aperture of the tube, when the animal 

 has retired into it*. 



The common species Serpula contortuplicata f, Ell. 

 Corall. xxxviii. 2., has round tubes twisted, and three lines 

 in diameter. Its operculum is funnel-shaped, and its gills 

 often of a fine red, or varied with yellow, or violet. It speedily 

 covers vAih its tubes, vases, and other objects, thrown into 

 the sea. 



We have, on our coasts, a smaller species, with a claviform 

 operculum, armed with two or three small points. {Serp. ver- 

 onicularis, Gm.) Mull. Zool. Dan. Ixxxvi. 7. 9. &c. The 

 gills are sometimes blue. Nothing is more agreeable to see 

 than a group of these serpulae, when they are well expanded. 



In others, the operculum is flat, and bristled with more 

 numerous points |. 



There is one in the Antilles {Serpula gigantea, Pall. 

 Miscell. X. 2. 10.) which sojourns among the madrepores, 

 and whose tube is often surrounded by their masses. Its gills 

 are spirally rolled when they re-enter the tube, and its oj)er- 

 culum is armed with two small, branching horns, hke the 

 antlers of a deer §. 



* The most common Ser[:)ula having this disc in the form of a funnel, 

 naturahsts have taken it for a proboscis, but it is not pierced, and the other 

 species have it more or less claviform. 



-f- It is the same animal as the Amphitrite penicillus, Gm. or Proboscidea,- 

 Bmg. Probosci-plectanas, Fab. Column. Aquat., c. xi. p. 22. 



;|: These are the Galeolaria, Lam. An operculum is visible on them, 

 BerL, Schr. IX. iii.6. 



§ Tlie same as Terebella bicornis, Abildg., Berl., Schr., IX. iii. 4. Seb. 



