224 PHOSPHORAX. 



221). It is P. ambigua, d'Orb., and P. Canariensis, Webb and 

 Berthelot. 



P. auriculata, Mousson ( unfigured), is considered by Wollaston 

 a variety of this species, and P. callosa, Mousson (unfigured), is 

 believed by Crosse and Wollaston, following the doubt expressed 

 in the original diagnosis, to have been described from a very old 

 individual perhaps abnormal. 



Unfigured and Undetermined Species of Parmacella. 



P. RUTELLUM, Hutton. Candaliar, Afghanistan. 



P. VELITARIS, Martens. Astrabad, Russian Armenia. 



P. CuMiNGir, Pfr. Isl. Juan Fernandez. 



P. GRACILIS, Gray. Hob. unknown. 



The genus, in the two latter species, is very uncertain. It is 

 scarcely possible that a native Parmacella would be found in 

 Juan Fernandez, and as the shell-plate only is described, it prob- 

 ably belongs to some other genus. 



Genus PHOSPHORAX, Webb and Berthelot, 1833. 



u It is not without some hesitation that I admit this species 

 into the Canarian catalogue; because M. d'Orbigny, on whose 

 authority it would seem to have been originally introduced (in 

 1819) into Ferussac's work, makes no allusion to it whatsoever 

 in his subsequent enumeration (in 1839) of the Mollusca of the 

 Canaries. It is highly probable, therefore, that he had some 

 actual reason for supposing that either the diagnosis or the 

 asserted habitat was inaccurate ; though if this was really the 

 case he ought to have stated plainly what the evidence was on 

 which it was allowed to appear in the ' Histoire Naturelle des 

 Mollusques.' Still, the fact remains that it is both described and 

 admirably figured in the latter magnificent publication, and that 

 nothing has yet been placed on record to call in question its 

 claims to be (as it professes) truly Tenerilfan. Yet the complete 

 silence of M. d'Orbigny concerning it in his after-list, and the 

 circumstance that it was established professedly on a unique 

 example (said to have been taken beneath dead leaves in the 

 mountains of Teneriffe) are points, so far as they go, to cast 



