1870.] Descriptions of neiu species of Diplommatince. 7 



rather pointed. "Whorls 8, lower tumid, sides rounded below, flat 

 above, penultimate the largest ; suture impressed, — a well marked 

 constriction of penultimate whorl situated close behind the peris- 

 tome, last whorl rises slightly on the penultimate ; aperture vertical, 

 circular, columellar, margin rather straight, tooth large, peristome 

 double, moderately thickened and continuous, forming a callus on 

 the penultimate. 



Height 0.23 ; diam. 0.13 ; diam. of ap. with peristome, 0.07. 



Habitat* — Burrail range near Nenglo, N. Oachar hills, in forest, 

 and as usual among decaying leaves. 



This species is a close ally of D. pachjcheilus, B s., partaking also 

 somewhat of the character of D. Blanfordiana, but tis a more tumid 

 form, and particularly the position of the constriction separates it 

 well from both those shells. 



Fifteen species of Diplommatina are now known from these hills 

 alone, and when the Graro hills have been explored, and the higher 

 portions of the Burrail and Patkoi ranges, Munipdr, &c, we may 

 expect more additions. Even now it establishes this region as quite 

 a centre of the genus, though I think it very possible many species 

 have escaped observation in other places, from the small size and 

 difficulty in finding these shells. 



Additional notes on Diplommatina, Alt/coeus, and Pup. imbricifera. 



On almost all the species of Diplommatina that I have examined a 

 constriction of the penultimate whorl is to be found, and in the larger 

 species it is very well developed. This constriction of the whorl 

 marks of course the position of the operculum when the animal is fully 

 withdrawn into, the shell, and the operculum of dead specimens 

 is also to be found at this point. It would appear from an examina- 

 tion of these shells, that the constriction also marks the commence- 

 ment of the formation of the columellar tooth. Behind the con- 

 striction the inside of the whorl appears thicker and is much 

 more polished; with the constriction this contracts, leaves the 

 outer surface of the shell and continues as a rim, like the sharp 

 tli road of a screw, running down and round the columella, 

 terminating on the columellar margin of the peristome in the more 



