Mr. W. H. Benson on new Cyclostomidse. 183 



elongate subturrited form at once distinguishes it from poly- 

 pleuris. 



Further specimens of D. pachycheilus, B., kindly sent to me 

 by Mr. H. Blanford, and contained also in the collection^ confirm 

 the characters given from a single specimen in the ^ Annals^ for 

 March 1857. In one specimen I find the striation exceedingly 

 minute^ closely set, and obliquely undulate. It occurs in the 

 Rungun valley, about the mineral spring of Sungtoot, in com- 

 pany with Streptaulus Blanfordi, B., which is found in crevices 

 and at the sides of large boulders of gneiss, in damp decaying 

 leaves, as reported by the discoverer. 



8. Pomatias Himalayce, n. s. 



Testa perforata, attenuato-turrita, solidiuscula, oblique confertim 

 crassicostata, albida, epidermide tenui pallida cornea induta ; spira 

 elongato-turrita, sensim decrescente, apice obtuse, sutura impressa ; 

 anfractibus 7-8 convexiusculis, ultimo rotundato, costis remotio- 

 ribus nonnullis intervenientibus, mox desinentibus, pone aperturam 

 munito ; apertura verticali, ovato-rotundata ; peristomate duplici, 

 incrassato, externo expanse reflexiusculo, interne continue, superne 

 ad angulum parietalem fissura minime profunda divise. Operculo 

 tenuissimo, membranacee, translucente, paucispirate. 



Long. 5^-10, diam. 2^-4 mill. Apertura majeris 3 mill, lenga, 2\ lata. 



Habitat cepiese in valle Rungun (4000 ped.) nee nen ad Darjiling 

 (7000 ped.). 



This shell seems to be an aberrant Pomatias, with reference 

 to the characters of the aperture. It enables me to assert that 

 the anomalous ribbed shell which, in its imperfect condition, I 

 assigned, in the 'Annals' for April 1857, to the genus Bulimus, 

 under the name of pleurophorus, belongs to the same operculated 

 genus as this species, with a stouter form and a thinner shell. 

 These examples occur far beyond the known limits of the genus 

 Pomatias, and encroach on the territories of Hydrocena, which, 

 in Oriental China, assumes a turrited form, but never obtains 

 the costulated sculpture of Pomatias. A single operculum con- 

 tained in the collection cannot be examined in order to ascertain 

 its internal structure ; but, on account of the double peristome 

 having the internal portion continuous, and of the costulation, 

 I have no hesitation in referring the species now described, and 

 its evident congener pleurophorus, to Pomatias, hitherto only 

 known as a Southern European form. The imperfect slit in the 

 parietal margin becomes occasionally obsolete. A young shell 

 is of a clear pale horn-colour. 



Descriptions of all the Alycai, Diplommatince, &c., hitherto 

 published will be found in Pfeiffer's ' Monographia Pneumono- 

 pomorum ' and the Supplement lately added. A number of 



