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POPULAR CONCHOLOGY. 



Philine. Ascanias. (Lobaria Mull. ; Bullaea Lam.) 

 — Shell concealed in the mantle of the animal, thin, 

 fragile, almost transparent, only slightly 

 involute, destitute of distinct spire, or 

 columella ; aperture very large and wide. 

 Animal, investing the shell, large, shiny; 

 capital disk oblong, or subquadrate ; no 

 eyes nor tentacula ; lateral lobes developed ; 

 foot not produced posteriorly ; branchial PMim 

 plume single ; gizzard armed with testaceous 

 plates ; tongue without axile teeth ; laterals in a single or 

 double file.* — Several species; also fossil. 



There are six British species, of which P. aperta is the 

 most common: it is found on all our coasts. P. hirun- 

 dinina is found on the coasts of the Isle of France, the 

 animal of which is of a beautiful blue colour. 



Doridium. Meckel. (Bullidium Meckel; Acera Cuv; ; 

 Lobaria Plain. ; Eidothea Pisso.) — No trace existing of a 

 shell. Animal, looking outwardly like that of Philine, 

 yet the sides of the foot have stronger and more wing- 

 shaped projections. — 2 species. 



Found in the Mediterranean. 



Gastropteron. Meckel. (Opiptera Rqfin; Sarcopterus 

 Rqfin ; Parthenopea Oken. ) — No trace existing of a shell. 

 Animal, the foot lengthened on each side into a very large 

 rounded wing, which can be thrown over the back, meet- 

 ing each other ; the head lobe is also thrown back on the 

 side, thus forming a tube ; the bulk of the body is oval ; 

 the gills lie free on the right side ; behind is a feather- 

 formed appendage ; there is no hard gizzard. 



One species, A. Meckelii of the Mediterranean. 



* Forbes's British Moll. 



