CONCHOLOGY. 15 



frequently in clusters spirally entwined, adhering to marine 

 substances. In colour they are brown, purple, yellow, 

 tawny, pink or white, and sometimes tinged with green. 



Tube solid, calcareous, irregularly twisted, fixed to other 

 substances. 



Serpula vermicularis. Serpula filaria. 



S, fascicularis. S. pellucida. 



S. intestinum. S. intorta. 



S. contortupUcata. S. cristata. 



S. plicaria. S. spirulaea. 



S. glomerata. S. quadrangularis. 



S. decussata. S. minima. 



S. protensa. S. echinata. 



S. infundibulum. S. sulcata. 



S. annulata. S. costalis* 



S. cereolus. S. dentifera. 



S. filograna. S. sipho. 



S. vermicella. S. arenaria. 



S. vermicularis. The worm-like Serpula. 

 White, cylindrical, tapering, rugged, variously curved and 

 twisted. 



3. Vermilia. Eight species. 



Tube testaceous, cylindrical, more or less twisted, grad- 

 ually attenuated posteriorly ; opening round, the margin with 

 one, two, or three teeth ; shell adhering by the side to other 

 substances ; provided with a convex operculum. 



Vermilia rostrata. Vermilia subcrenata. 



V. triquetra. V. plicifera. 



V. bicarinata. V. scabra. 



V. eruca. V. taeniata. 



V. triquetra. The three-sided Vermilia. 

 White or reddish, rugged, twisted and triangular, cari- 

 nated along the back. 



