174 LIMNEA. 



1. Cryptella. Spire mammillated ; a septum. Fig. 256. 



2. Parmacella. Flat, haliotoid, spiral. Fig. 257, 258. 



3. Testacellus. Sub-spiral. Fig. 261. 



4. Limax. Incomplete. Fig. 259. 



5. Plectrophorus. Conical. Fig. 260. 



6. Vitrina. Heliciform, hyaline. Fig. 262, 263. 

 LIMACINEA. Bl. The third family of the order Pulmobranchiata, 



Bl. Described as containing shells very variable in form, most 

 frequently inclining to globular or oval ; the apex always obtuse ; 

 aperture variable, but never emarginated. All the Limacinea 

 are phytophagous and terrestrial. This family answers to the 

 genus Helix of Linnaeus and to the Colimacea of Lamarck, leaving 

 out the Auriculacea. It contains the genera Succinea, Bulinus, 

 Achatina, Clausilia, Pupa, Partula, Helix, Vitrina, Testacella, 

 Limacella, Limax. 



LIMAX. Lam. Limacinea, Lam. and Bl. — Bescr. Internal irre- 

 gular, sub-quadrate, scutiform, crystalline ; apex rounded, in- 

 distinct ; epidermis, light brown, thin, extending beyond the 

 margin. — Obs. The shell is placed under the scutellum of the 

 common garden slug. Fig. 25, L. Antiquorum. 



LIMNACEA. Bl. The first family of the order Pulmobranchiata, 

 Bl. The shells of this family are described as thin, with the 

 outer lip always sharp. It contains the genera Limnea, Physa, 

 Planorbis. 



LIMNEANA. Lam. A family of the order Trachelipoda, Lam. 

 containing the following genera: — 



1. Limn^ea. Spire produced ; including Physa. Fig. 308 

 to 310. 



2. Planorbis. Spire orbicular ; including Planaria. Fig. 

 311, 312. 



LIMNEA. Lam. (Ajjuvae, limnas, lacustrine.) Fam. Limnacea, Lam. 

 and Bl. — Descr. Oblong, light, thin; spire variable in length, 

 acute ; last whorl large, aperture large, longitudinal, entire ; inner 

 lip spread over a portion of the last whorl ; columella forming an 

 oblique fold ; outer lip rounded at each extremity, thin. — Obs. 



