214 Land and Fresh-water Shells of the Himdlaya. [March, 



spective species are like the outposts of hostile armies, ready to profit 

 by every slight change of circumstances in their favour, and to advance 

 upon the ground occupied by their neighbours and opponents* — T. H. 



No. 1. Helicarion cassida, Hutton. — Testa ovato-depressa, pallide 

 cornea radiatim striolata, junioris epidermide sericea, aetate nitore orba- 

 ta, anfractibus (penultima etiam intra aperturam) ventricosioribus ; 

 apertura patula, rotundato-ovata ; spira convexa, apice exsertiuscula, 

 minine obtusata, anfractibus 5 velociter crescentibus. — (B.) 



Greatest breadth 1 inch 2 lines. 



This shell has a more exserted spire than any other species known 

 to the writers. This character, notwithstanding the great size of the 

 aperture, coupled with the ventricose appearance of the penultimate 

 whorl within the aperture, gives the shell an Heliciform air. It is very 

 closely allied in habit to a species lately received from Almorah, but 

 differs from it in its greater size and paler color, and in the want of 

 the polish which is observable in the Kemaon shell. It equals in mag- 

 nitude the Sylhet " Vitrina gigas" from which singular Macrostoma- 

 tous species it altogether differs in form. — (B.) 



At Simla it is not uncommon during the rains, or even after heavy 

 showers at other seasons, creeping out from the holes of stone walls 

 and the crevices of rocks with the grey colour of which its own hue 

 assimilates so much when concealed by its mantle, that it is not easily 

 discovered. It occurs from Bhar to Simla but most abundantly be- 

 tween the former place and Subathu, 



Animal varying in colors, sometimes pale brownish, at others dark 

 grey. Two broad leaf-like processes running to a point, are spread 

 over the shell when the animal is in motion, so as entirely to conceal it, 

 and presenting the appearance of a large grey slug with a hump-back ; 

 a fleshy anal horn, as in the genus Nanina ; foot very long ; tentacula 

 4, the superior pair longest ,buttoned at the tips and bearing the eyes. 

 Orifice on the right side below the leaf-like process. 



Shell large, of 5 whorls, ventricose, suddenly increasing, the body 

 whorl forming nearly all the shell. Transversely wrinkled by the lines 

 of growth ; aperture transverse, ovate, broader than long, discovering 

 the previous whorls ; margins acute, interrupted on the body whorL 

 Epidermis varying in colors from yellowish to olive green. In young 

 specimens lustrous when placed on its spire, the aperture appears as if 

 the pillar lip had been obliquely sliced off. The animal carries the 

 shell horizontally on its back, the spire pointing upwards. — (H.) 



* Lyjell's Geology, vol. II. page 172. 



