243 



ADDENDA 



EMENDATIONS 



The British Dentalium Dentalis is not that described 

 by Linnceus but is the Tarentinum of Lamarck. This 

 conclusion is made from a comparison of Turton's speci- 

 men with the Mediterranean species. 



SPIRORBIS. CONICA. HETORODISCA. C. Flem. 

 Edin.Enc. *.205./. 3. Fl Ed. Phil. j. vol. 12. 

 p. 247. Sinistral, strong, hyaline, triangular. 



When young the upper part of the whorl has a dis- 

 tinct groove with a low acute ridge on each side and a 

 very small central cavity. In this state the whorls are 

 two in number, the outer one lateral with a spreading 

 base. The third whorl in its growth not only embraces 



