CLAUSILIA. 285 



granular, with rather tumid bulbs ; lower pair more conical 

 and deeply coloured than the upper ones, and nearly smooth : 

 foot broad and rounded in front, transversely grooved at its 

 sides, and ending in a slender but blunt tail. 



SHELL of the same shape as C. biplicata, but semitranspa- 

 rent and glossy, yellowish-brown with a faint tinge of red, 

 smooth to the naked eye, but under a magnifier delicately 

 striate in the line of growth, these striae being more percep- 

 tible near the suture ; there are also a few coarse wrinkles 

 near the mouth and umbilicus, besides irregular pit-marks 

 dispersed over the surf ace : periphery much more rounded than 

 in any of the foregoing species : epidermis thin : whorls 1 2, 

 compressed, the last scarcely exceeding one-fourth of the 

 shell and a little narrower than the preceding whorl ; the first 

 two or three whorls are nearly of the same size and form a 

 short cylinder : spire slender and gradually tapering, obtuse at 

 the point : suture rather oblique and slight : mouth oval or 

 inclined to quadrangular, broad, rounded and effuse at the base, 

 and not acutely angled above ; columellar teeth more strong 

 and prominent than in any of the other species which have 

 been above described; there are three or four labial or palatal 

 folds, which are conspicuous outside, owing to the shell being 

 nearly transparent ; but there are no intermediate denticles 

 between the columellar folds, nor any lunella : outer lip white, 

 expanded and thick : basal crest slight : umbilicus very small : 

 clausilium squarish-oblong, flexuous, with a deep notch on its 

 side near the base. L. 0*7. B. 0'15. 



Var. 1. pellucida. Shell thinner, more transparent, and 

 very glossy. 



Var. 2. albida. Shell greenish- white. 



HABITAT : On the trunks and at the roots of trees 

 (especially the beech and ash), as well as among dead 

 leaves, and occasionally on mossy rocks, in woods 

 throughout a considerable part of these islands, from 

 Northumberland to Devon, and also in South Wales and 

 Ireland, but not everywhere. Var. 1. Penrice, Glamor- 

 ganshire (J. G. J.). It is rather difficult to account for 

 the thinness of these shells, as they were found in a 

 limestone district, and calcareous material was therefore 



