82 LIMACID^. 



OoPELTA, Moi-ch, 1861. 



Distr. — Java, Ceylon, Cape of Good Hope, Guinea. 0. nigro- 

 punctata^ Moreh. 



Body limacLform, subcylindrical, tapering behind ; tentacles 

 simple; mantle small, oval, more pointed behind; no longitu- 

 dinal furrows above the margins of the foot, and no caudal mucous 

 pore ; no distinct locomotive disk ; external respiratory and 

 anal orifices on the right slightly anterior margin of the mantle ; 

 orifice of combined generative sj^stem behind and under the right 

 eye-peduncle. 



No internal shell-plate. 



Jaw smooth, with a median projection. 



Lingual naembrane with tricuspid centrals, bicuspid laterals, 

 quadrate marginals. 



The two following genera, together with Selenites, Fischer 

 {Helix concava, Say), constitute the famil}'- Selenitid®, Fischer, 

 characterized by the dentition of Testacella united to the jaw of 

 Limax. The elements thus united appear to me to be other- 

 wise too incongruous. If such characters are sufficient for the 

 formation of families, then Cystopelta, Tate, would require a 

 new family also, having the teeth of Testacellidge with the ribbed 

 jaw of Arion ; and so we might multiply families ad infinitum. 



Plutonia, Stabile, 1864. 



Syn. — Yiquesnelia, Morelet (not Deshayes). 



Dist. — P. Atlantica, Morelet. Azores. 



Body compressed behind, carinated, rugose ; mantle median, 

 free in front, with posterior pulmonary orifice ; posterior 

 extremity subtruncated, without mucous pore ; jaw without ribs 

 or median rostriform projection ; teeth like Testacella. Internal 

 shell-plate oblong, Ancyliform, with a rudimentary spire. 



The shell of this genus was considered 'by Morelet and Drouet 

 a recent representative of the genus Viquesnelia, Desh., 185T ; 

 a name given to certain fossils of the nummulitic beds of Rou- 

 melia. The identification is, however, imaginary. 



Trigonoohlamys, Biittger, 1881. 



Dist. — T. imitatrix^ B'ittg. Caucasus. 



Animal limaciform, with two dorsal and two lateral grooves, 

 directed from the mantle towards the head ; mantle behind the 

 middle of the body ver^^ small, attached all around, granular ; 

 anal and respiratory orifices behind the right margin of the 

 mantle ; tail short, compressed, carinated, without mucous pore ; 

 jaw similar to that of Parmacella, radula to Testacella. No 

 internal shell ? 



