l48 UNIVALVES. SERPULA* 



prickles; it is usually of a rosy or pink color, and some- 

 times has its aperture nmrgined. 



The Serpula cornucopiae, or horn of plenty, is, in all 

 probability, only a dropped helix hortensis, or common 

 garden snail, and of course not belonging to this genus. 

 The Serpula infundibulum appears as if its first bend 

 was composed of five funnels, inserted within each other. 

 The Serpula denticulata is sometimes found in the lepas 

 tintinnabulum; and the Serpula sulcata adheres to the 

 roots of the fucus digitatus. The Serpula lagena is ex- 

 actly like an oil-flask, and the Serpula retorta is retort- 

 shaped; the latter is scarce. The Serpula incurvata 

 something resembles the nautilus semilituus, but it wants 

 the internal concamerated structure. The Serpula nau- 

 tiloides is a spiral shell, flattish, minute, and is furnished 

 with thin, semilunar, internal divisions. 



The colors of the Serpulae are various; the most gene- 

 ral, however, are brown, purple, yellow, tawny, pink, 

 and white, sometimes a little greenish. The Serpula 

 semilunum, and Serpula Melitensis, are found fossil ; the 

 latter in Malta. 



The Indian, African, American, and Northern oceans, 

 supply many species ; as also do the European, Mediter- 

 ranean, Adriatic, and Red seas. 



SERPULA. —Worm-Shell. 



Nautiloides. *Triquetra. 



Semilunum {Small Seed.) *Intricata. 



Planorbis. Filograna. 



Spirillum. Granulata. 



*Spirorbis. ^Contortuplicata- 



