188 LIMACTDvE. 



Genus PARMACELLA, Cuvier, 1805. 



Animal limaciform, cylindrical, swollen behind, gradually 

 attenuated in front, with a very long neck ; without mucous 

 pore ; shield central, large, a large portion of the margin free, 

 finely granular, concealing the shell-plate ; pulmonary orifice on 

 the posterior right margin of the shield ; genital orifice behind 

 and below the right eye-peduncle. Jaw smooth, arcuated, 

 slightly rostriform in the middle. Lingual membrane with tri- 

 cuspid central and first lateral teeth, the marginals narrow, 

 bicuspid, but the exterior cusp short. 



Shell small, testaceous, internal, with subspiral nucleus, the 

 aperture very large, dilated anteriorly. 



Mediterranean countries, Western Asia, Canary Islands. 



Fossil in the Miocene of the Rhone Basin. 



Subgenus CRYPTELLA, Webb and Bertholet, 1833. 



Shell less distinctly spiral. Canary Islands. 



Scarcely distinguishable from the type. 



Genus PHOSPHORAX, Webb and Bertholet, 1833. 



Animal limaciform, swollen in the middle; mantle large, 

 anterior, with a small posterior phosphorescent disk upon it, 

 concealing a shell-plate ; no longitudinal furrows above the mar- 

 gin of the foot, and no caudal mucous pore (?) ; distinct locomo- 

 tive disk (?); respiratory orifice on right anterior margin of mantle. 

 Jaw and lingual membrane unknown. Internal shell-plate thick, 

 oval, testaceous. The single species, only known from a figure 

 published many years ago, is said to inhabit Teneriffe. 



Genus OOPELTA, Morch, 1867. 



Animal limaciform, attenuated behind, without mucous pore ; 

 shield small, oval, granulated ; respiratory orifice a little anterior. 

 Jaw smooth, with a slight projection of its median margin. 

 Radula like Helix, the marginal teeth obtuse (PL 44, fig. 5). 



No internal shell. A single species inhabits Guinea. 



This remarkable mollusk unites the external appearance and 

 jaw of Liinax with the dentition of Helix, and has no shell-plate. 



