HELICIDJE. 187 



Mr. Alder most justly observes, that B. articulates 

 of Drap. is only a common variety of B. acutus. But 

 the specimens of B. articulatus of Turton, which are 

 now in the cabinet of Mr. Clark of Bath, accord- 

 ing to the observations of Mr. Alder, are a very dis- 

 tinct species, not known, he believes, to inhabit Europe. 

 Dr. Turton admits this species and B. ventricosus 

 into the Fauna, as having been sent him " from the 

 plains about Penzance in Cornwall," but without 

 stating by whom they were found, or how transmitted 

 to him. 



The Bulimus articulatus of Turton (Man. ed. 1. p. 

 6. f. 68.), judging from the figure, is a West Indian 

 species, named by Mr. Guilding Macroceramus sig- 

 natus. (Seep. 20. n.5.) 



8. ZUA Leach. (Varnished Shell.) 



Animal like Bulimus, with an ovate subcylindrical 

 rather blunt shell, covered with a smooth polished 

 periostraca; mouth ovate, thickened, and united 

 all round; peristome toothless; axis imperforated. 



This genus is easily known from Bulimus by the 

 polished periostraca and continued, thickened, not 

 reflexed lip; and from Azeca by the simple peri- 

 stome. 



Mr. Jeffreys has established a genus under the 

 name of Cionella for this species and Achatina aci- 

 cula ; but these shells appear to have no natural 

 alliance to one another, and the characters given 

 to the genus are hardly such as could distinguish a 

 species. 



