?6 LAND AND FRESH-WATER SHELLS. 



pale grey or cream colour ; slime milk-white. Shell small, oval, 

 thin ; margin membranaceous. Length J to i^ inches. Fields, 

 gardens, woods. Very common. A. agrestis.* 1 



(b] Animal dark brown, slender, very glossy ; mantle very tumid 

 behind, pale yellowish-brown ; sole ash-coloured ; slime almost 

 colourless. Shell unguiform, convex above, flat beneath, solid ; 

 margin not membranaceous. Length | to fths inch. In damp 

 situations. Moderately common. A. Icevis. 



Family III. Testacellidae. 



Shell small, auriculate, external, placed on the hinder portion 

 of the body, covering the mantle ; respiratory orifice on the right 

 side below the mantle. 



19. Testacella. 



(a) Shell roundish-oval, depressed; whorls one and a-half, the 

 nucleus making an angle of 45 to the vertical line ; spire short ; 

 suture deepish ; mouth roundish, dilated in front. Length \ to fths 

 inch. Animal with two longitudinal furrows on its back, which 

 commence from the shell and terminate near the head. Market 

 gardens and fields. Local. T. haliotidea. 



(f] Shell resembling that of 2\ haliotidea but smaller in propor- 

 tion to its length, flatter on its superior surface, comparatively 

 longer, more wedge-shaped, brownish, lines of growth finer and 

 less rugged, thinner, and the left side of the shell is more strongly 

 curved. Animal slightly more attenuated in front, and the longi- 

 tudinal furrows near the mantle are much closer together. The 

 nucleus of the shell is placed at an angle of 60 or 70 to the 



Fig. 30. Testacella haliotidea. 



47 v. filans, greyish-white or ashy, mantle yellowish ; v. nigra, jet-black, 

 tentacles bluish or brownish-black, sole pale ; v. sylvatica, greyish, mottled; 

 v. punctata, greyish-white, minutely spotted with black ; v. tristis, brownish, 

 mantle with two lateral brown bands, and sometimes a third intermediate 

 band; v. cineracea, greyish-white, mantle ashy (type); v. submaciilata, 

 greyish-white, streaked with seal-brown on the back which extends on to the 

 posterior frds of the mantle, the sides of the body and anterior rd of the 

 mantle are free from streaks and spotted with black. 



