142 GENUS XXXIV. SERPULA. 



Vermicularia. Shell tubular, turned spirally at its origin, 

 entire through its whole length, the opening simple and 

 round (see S. Imnbricalis, pi. 9. /. 132). 



Serpula. a tubular, adherent, calcareous tube, variously 

 twisted or grouped, fixed to marine bodies (see S. glome- 

 rata, pi. 9. /. 133). 



SiLiQUARiA. A tubular shell, spiral at its beginning, conti- 

 nued in an irregular form, being divided laterally through 

 its whole length by a narrow slit (see S. anguina, j)l. 9. 



/. 131). 

 Spirorbis. a solid testaceous tube, regularly turned spirally, 

 wheel-shaped, adhering to marine bodies (see S. Spiroi^bis, 

 pi. 9. /. 134). 



Lamarck arranges Serpula and Spirorbis along with his 

 Vermes. 



