THE NAUTILUS 



VOL. XXIX. NOVEMBER, 1915. No. 7 



A NEW INDIAN SPECIES OF PUPILLID.E. 



BY H. A. PILSBRY. 



BIFIDARIA (BENSONELLA) LANDURENSIS n. sp. 



Shell rimate, the rimation like a reversed comma, conical, 

 brownish corneous, glossy and smooth except for faint growth- 

 strise; the apex obtuse, whorls 5, convex, the latter part of the 

 last whorl straightened, slowly ascending. Aperture heart- 

 shaped, vertical, obstructed by three lamellse upon the parietal 

 wall, two on the columella, and four acute folds or plicae within 

 the outer and basal margins. Angular lamella not quite margi- 

 nal, simple continuous and deeply entering; parietal lamella 

 higher and thicker, not emerging quite so far, and also very 

 deeply entering; infraparietal lamella quite small and short, 

 more immersed. Columellar lamella deeply immersed, smaller 

 than the parietal. Infracolumellar lamella small, tubercular, 

 deep within. Plicae all remote from the margin, the lower 

 palatal largest, the basal, upper palatal and suprapalatal some- 

 what smaller, all lamellar. Peristome very narrowly expanded, 

 having a perceptibly thickened rim within the basal and outer 

 margins, terminating in a white tubercle above the middle of 

 the outer lip. Above this tubercle the lip is thin and strongly 

 arcuate. Length 2.2, diam. 1.5 mm. 



Landour, India, with B. plicidens Bens. Type no. 16721 A. 

 N. S. P. This species is perceptibly smaller than B. pliadens, 



