CLAUSILIA. 175 



3. C. biplica'ta,* Montagu. Pl. IX. 



Body reddish-grey, blackish above, hghter underneath, rather 

 strongly tuberculate ; tentacles very slightly transparent, of a 

 dirty reddish colour, upper pair subcylindrical, shagreened, 

 diverging, bulbs slightly swollen, lower pair considerably diverg- 

 ing, bulbs indistinct : Joot long, somewhat slender, sole of a 

 uniform ashy-grey with minute milk-white specks. Viviparous 

 (Rich). 



Shell somewhat spindle-shaped, slender, moderately thin, 

 scarcely semitransparent, rather glossy, brown with a reddish or 

 yellowish tinge, with strong, close-set, slightly curved striae in the 

 line of growth, some of which are streaked with white ; periphery 

 bluntly angulated ; epidermis thickish ; whorls 12-13, com- 

 pressed ; spire tapering, apex obtuse and (as are also the two 

 whorls below it) smooth and glossy ; suture rather shallow, 

 somewhat oblique; mouth pear-shaped, contracted and channelled 

 below, folds similar to those of the preceding species, except 

 that the small teeth or ridges between the folds on the base 

 of the penultimate whorl are usually absent ; outer lip white, 

 moderately thick, broad, detached ; basal crest prominent, nearly 

 straight ; clausium oval, slightly curved. 



The following are the only localities in which this 

 species has as yet been observed in this country : — 

 Easton Grey, Wilts (Montagu), Clarendon, near Salis- 

 bury (Bridgeman), and near Hammersmith. It is to 

 be found at the roots and on the bark of willow trees, 

 and among moss on banks. The shell is much longer 

 and less ventricose than that of C. Rolphii, from which 

 it also differs in being streaked with white, and in 

 having its aperture channelled at the base. 



Var. Nelsoni. — " Shell rather more slender than the usual 

 form, almost totally devoid of striation, and translucent, the axis 



* With two folds. 



