266 Mr. W. H. Benson 07i new Helicidse. 



From the clear horn-coloured Heliw fastipata, Hutton, of the 

 Western Himalaya, it may be known by its narrower spire, de- 

 cided sculpture, minute size, the absence of a marginate suture, 

 and by its perforate base; and from the dark-coloured H. Bar^ 

 rakporerisis, Pfr., of the Sikkim Terai, by the first three cha- 

 racters. 



3. Helio! Rimicola, nobis, n. s. 



Testa vix perforata, orbiculato-pyramidata, tenui, fragili, oblique 

 striatula, diaphana, pallida cornea; spira conica, apice obtuse, 

 sutura leviter impressa; anfractibus 5^ convexiusculis, ultimo 

 convexo, compresse rotundato ; apertura obliqua, subquadrato- 

 lunari, peristomate tenui, recto, margine columellari vertiealiter 

 descendeute, basali arcuato. 



Diam. major A^, minor 4, axis 4 mill. 



Var. peripheria primo subangulata, angulo versus aperturam 

 evanescente, in juniori magis conspicuo. 



Habitat forma typica prope Landour Himalayse occidentalis, Tarietas 

 in valle Rungun prope Darjiling, rarissime. 



I got a single fresh specimen of this fragile species, in Octo- 

 ber 1842, in a precipitous rift at the back of the Seinty or 

 Queinty ridge, eastward of my grounds at Rockville, near Lan- 

 dour, and at an elevation of nearly 7000 feet. The Messrs. 

 Blanford have lately procured the variety, but rarely, and in a 

 dead state, in the Rungun Valley in Sikkim, at an elevation of 

 4000 feet. From the data furnished by Mr. W. T. Blanford 

 respecting the resort of species at Darjiling, I observe that the 

 same forms evince a disposition to descend there to a lower alti- 

 tude above the sea than in the western portion of the range — a 

 circumstance attributable probably to the greater moisture of the 

 climate, — whereas the drought and hot winds, which prevail for 

 so many months in the year at the base of the western ranges, 

 drive species to a greater height in order to obtain the humidity 

 necessary to their existence. At Landour this form escaped the 

 active researches of the late Dr. J. F. Bacon ; and I am not 

 aware of its having yet occurred to Capt. T. Hutton. 



4. Helix rorida, nobis, n. s. 



Testa subperforata, globoso-depressa, tenuissima, minutissime radiato- 

 striatula, polita, pellucida, fusco-cornea ; spira depresse conoidea, 

 apice obtuso, sutura impressiuscula, tenui-marginata ; anfractibus 

 4 convexiusculis, ultimo ad peripheriam convexo, subtus convexi- 

 usculo ; apertura obliqua, subrotundato-lunari, peristomate tenui, 

 recto, margine columellari verticali, arcuato, superne brevissime 

 reflexo, perforationem fere celante. 



Diam. major 5, minor 4^, axis 2| mill. 



Habitat ad Darjiling, necnon ad collem Sunhul. 



Independently of its smaller size, translucent dark corneous 



