98 Mr. W. H. Benson 07i a new Pupa and a new Bulimus. 



apice obtuso ; anfractibus 6| convexis, ultimo } totius lougitudinis 

 eequante, antice leviter adscendente, basi circa umbilicum vix com- 

 pressiuscula ; apertura truncato-ovata, 3-plicata, obliqua ; peristo- 

 mate simplici, disjuncto, acuto, albido, marginibus expansiusculia, 

 exteriori superne valde arcuato, labio subreflexo ; plica unica in 

 medio parietis, columellari 1 obliqua obtusata brunnea, palatali 1 

 elongata, albida ; extus sulcum eifbrmante, omnibus profundis. 



Long. 2, diam. | mill. 



Hab. in regione Riviera Pedemontana ad basin coUium prope Nizzs 

 maritimam sub lapide. 



In form, size and sculpture approaching most nearly to the 

 edentate P. minutissima, but more slender than that species. It 

 is singular that this beautiful little shell should have escaped the 

 researches of Risso, none of whose doubtful species exhibit any 

 approach to it. 



It differs from triplicata, Studer, in its much smaller size, 

 more slender cylindrical form and stronger sculpture, in the 

 greater comparative size of the columellar plait, in the transverse 

 position of the parietal plait, and the more deeply set palatal 

 tooth, which in some aspects is not visible from the aperture. 

 It is also deficient in the stricture and callus observable behind 

 the outer lip in adult specimens of that species. As in P. tri- 

 plicata, and partially in the South African P. fontana, the palatal 

 tooth causes a furrow on the outside of the lower whorl. The 

 costulse are flattened and narrow, and the intercostal spaces 

 double the breadth of the ribs. 



It has a whorl more than P. Ascaniensis, A. Schmidt, is larger 

 and more lengthened in form, the forms and proportions of the 

 teeth differ, and its peristome, which is fully formed, has no re- 

 semblance to that of the Aschersleben species. The sculpture, 

 moreover, is more delicate, and the whorls more ventricose than 

 in Archdeacon Schmidt's late interesting addition to the German 

 fauna. 



In M. Albin Gras' Mollusca of the Department of the Isere, 

 his figure of P. muscorum, Michaud, var. k deux dents, pi. 4. 

 f. 18, from the Bastille near Guy Pape, approaches P. Rivierana. 

 He notes one tooth on the columella (the plate shows it to be 

 parietal), and one on the lower edge (the plate shows this to be 

 within the outer lip near the base, not deeply placed in the centre 

 of the lower whorl, as in Ascaniensis and Rivierana). In the 

 description M. Gras makes no mention of the sculpture, and no 

 strise or costulse are observable in the plate, while the obtuse 

 plait on the columella of P. Riviei'ana appears also to be defi- 

 cient. Pfeiffer and Kiister both refer Michaud's P. mxtscorum 

 to minutissima, together with Draparnaud's shell, in which that 

 author notices a slight parietal plait. Risso's P. muscorum is 



