444 Mr. W. T. Blanford on the Classification of 



D. Kingiana from the Kolamully Hills, are distinguished by 

 their cylindrically-ovate form, smooth whorls, continuous cir- 

 cular peristome not expanded into a callus upon the penultimate 

 whorl, by the absence of a columellar tooth, and by the regular 

 convexity of the sides of the spire. The earliest described spe- 

 cies, Z>. folliculus, Bens., and its congeners in the Western Hi- 

 malayas, D. costulata, Bens., and the sinistral D. Huitoni, Pfr., 

 are to some extent intermediate between the two types; but 

 they approach less nearly, in their costulated whorls, more acu- 

 minate spire, and less circular mouth, to the Peninsular forms 

 than to those of the Eastern Himalaya*. 



I have lately found, in the Western Ghats near Bombay, a 

 very peculiar minute species, belonging to the Peninsular type, 

 but distinguished from every other form in the genus by pos- 

 sessing spiral sculpture. 



3. Opisthostoma, H.Blanf. 



Since the discovery of the minute 0. Nilgiricum, described by 

 my brother, Mr. H. F. Blanford, in the 'Journal of the Asiatic 

 Society of Bengal' for 1860, no additional form of this most 

 remarkable genus has been met with, nor do any more specimens 

 appear to have been collected. 



In the ' Malakozoologische Blatter' for the present year (p. 39), 

 Dr. Dohrn, reviewing our papers, considers this form as probably 

 belonging to the Pupinida, and remarks especially on its resem- 

 blance to the Philippine Arinia, This tends to confirm our 

 belief in its Cyclostomaceous affinities, of which, indeed, there 

 can be little doubt ; but the position of Arinia itself is far from 

 being satisfactorily determined, and it is classed by many writers 

 [e.g. Pfeiffer and Adams) with Diplommatina. It appears pro- 

 bable that, in all the characters which tend to connect Opistho- 

 stoma with Arinia, the former shell approaches equally to certain 

 forms of Diplommatina, partly t» the Indian forms, and also in 

 some respects to the sinistral group of Australia. In its costu- 

 lation and minute size, Opisthostoma certainly approaches Di- 

 plommatina, and differs from the Pupinidse, which are mostly 

 characterized by the absence of sculpture. The last whorl in 

 many species of Diplommatina rises so far in front of the shell 

 as almost to touch the antepenultimate ; so that it is easy to 

 understand the connexion with the singular distortion of the 

 last whorl of Opisthostoma, which, on the other hand, has no- 

 thing approaching to the peculiar slits and tubes characterizing 

 the aperture of most of the Pupinidse. 



* This is by no means the only instance in which the land-shells of the 

 Western Himalaya are more nearly allied to those of India proper than 

 are the species inhabiting the same mountains further east. 



