102 LIMN^ID^. 



Amphipeplea, Nilsson, 1822. 



Syn. — Myxas, Leach, teste Turton, 1831. 



Bistr. — 18 sp. Europe, East Indies, Australia, Philippines. 

 A. glufinosa^ Miill. (ciii, 10). 



Shell globular, ventricose, thin, transparent ; spire ver}^ short, 

 depressed ; aperture very lai-ge ; columella without fold ; outer 

 lip sharp. 



Animal with the mantle-margins developed, partly covering 

 the shell ; tentacles flat, triangular. 



Erinna, H. and A. Ad., 1858. 



Bistr. — Sandwich Islands, Isle of Bourbon. E. Newcomhi\ 

 H. and A. Ad. (ciii, 11). 



Shell semigiobose, thin, horny, olivaceous, longitudinally finely 

 striated ; spire very short, obtuse, apex rather eroded, last whorl 

 ventricose; aperture large, semiovate ; inner lip posteriorly 

 ascending on the body-whorl; columella straight, excavated, 

 and with a curved, elevated, external ridge continued in front 

 into the outer lip, which is simple and acute. 



The shell much resembles Lithotis, Blanford, but the descrip- 

 tions of the animals differ. 



Lantzia, Jousseaume, 1812. 

 Bidr. — L. carinato,^ Jouss. Isle of Bourbon. Living in moss, 

 at 1200 metres altitude. 



Shell auriform, with very short spire, last whorl triearinate ; 

 peristome thickened within; columellar lip flattened, forming a 

 septum. Foot large ; tentacles flattened, triangular, with eyes 

 on prominences at their base, interiorly ; jaw fibrous, of three 

 segments. 



? Canefria, Issel, 1814. 



Bistr. — G. spJeiidens^ Issel. Borneo. 



Shell small, cjdindrically conical, summit truncated by erosion, 

 suture lacerated, irregular, aperture entire, without plications or 

 teeth, lip simple. 



Appears to partake somewhat of the characters of Auricula. 



Physa, Draparnaud, 1801. 



Etym. — Physa., a pouch. 



Syn. — Rivicola, Fitz., 1833. Isidora. Hald. 



Bistr. — 100 sp. North America, Europe, East Indies. Fossil, 

 43 sp. Wealden — , Europe ; Cretaceous — , N. Am. P. ancillaria, 

 Say (ciii, 12). P.fontinalis^ Linn, (ciii, 13). 



Shell ovate, sinistrally spiral, thin, polished ; aperture rounded 

 in front. 



Animal with long, slender tentacles ; the eyes at their bases ; 

 mantle-margin expanded and fringed with long filaments. Jaw 



