CLADOPODA. 359 



Genus SERPULORBis, Sassi. 



Foot truncate, radiated at the end, the front part pro- 

 duced into tentacular processes. 



Operculum none. 



Shell tubular, irregularly twisted, attached ; aperture 

 circidar, peritreme acute, continuous. 



Si/n. ? Lementina, Risso. Serpuloides, Gray. Ha- 

 tina. Gray. 



Ex. S. gigas, P/nlippi, pi. 39, fig. 2. Shell, S. gigas, 

 fig. 2, a. 



The genus Lementina of Risso is most probably a 

 badly-observed and incorrectly-figured S. arenaria, an 

 inhabitant of the Mediterranean. 



Species of Serpulorbis. 



arenaria, Chiaje. iuoperculata, Riipp. 



dentifera, Quay and Gaim. varians, D'Orb. 



gigas, Phil. 



Genus CLADOPODA, Gray. 



Foot elongate, front end simple, hinder extremity ob- 

 long, clavate, or subtruncate. 



Operculum none. 



Shell tubular, irregularly subspirally twisted, whorls dis- 

 united ; aperture round, peritreme acute, continuous. 



Syn. Vermetus, sp. Quoy and Gaimard. 



Ex. C. arenaria, Quoy and Gaimard, pi. 39, fig. 3. 

 Shell, C. Quoyi, H. and A. Adams, fig. 3, a. 



In this genus, the species of which are chiefly from 



