84 COLIMACEA. 



This species may be confounded with its congeners, but will 

 be distinguished from H. nitidula, ccllaria, and alliaria, by its 

 greater convexity, its more regular striae, darker colour, and in 

 being devoid of the opaque whitish aspect of its base. 



This is a rare and local species. It has been met with near 

 Wolverhampton ; Tenby, Wales ; in the neighbourhood of 

 Shrewsbury, and near Newcastle-upon-Tyne. Mr. Thompson 

 remarks that it appears to be rare in Ireland, as well as in 

 England. He gives as localities, in the rejectamenta of the 

 rivers Lagan and Blackwater, near Belfast ; also near Portar- 

 lington and Finnoe, north of Tipperary. 



35. Helix radiatula, pi. IX, f. 9? 10. 



Helix radiatula, Alder, Cat., p. 12, No. 50; lb,, Mag. Zool. 

 and Dot., II, p. 107; Jeffreys, Linn. Tr., XIII, p.511 ; Thomp- 

 son, Ann. and Mag. Nat. Hist., VI, p. 33 ; Brown, Illust. Conch., 

 p. 53, pi. 18,* f. 5, 6; Helix striattila, Gray, Med. Rep., 1821, 

 p. 239 ; Helix brevipes, Turton, Man., p. 65, pi. 5, f. 50. 



Shell pellucid, diaphanous, horn-coloured, depressed ; spire 

 but little elevated above the body volution, and consisting of 

 three volutions, which are particularly flat at their junction ; 

 body large, in proportion to the spire ; upper parts covered 

 with regular, continuous, longitudinal striaj, and producing a 

 radiated appearance ; base smooth, with a moderately sized 

 umbilicus. This is an exceedingly minute species, its diameter 

 hardly exceeding the twentieth of an inch. 



Its habitat is in wet mossy ditches, and in damp wooded 

 localities. 



Distinguished from the young of H. zonites, by the great 

 flatness of the volutions at their lower side, and by the striaa 

 being more regular and decided. 



This shell occurs in many parts of Britain. Mr. Thompson 

 gives as localities, Dovedale, Derbyshire ; the Falls of Clyde, 

 Lanarkshire; and Ballantrae, Ayrshire; and in Ireland, he says 

 it is widely distributed, namely, Londonderry, near Dublin, 

 Downshire, Antrim, Tyrone, Cork, and Queen's County. 



36. Helix crystallina, pi. IX, f. 11, 12. 



Helix crystallina, Muller, Verm., II, p. 23, No. 223; Pfeiffer, 



I, p. 46, pi. 2, f. 36; Drapernaud, p. 118, pi. 8, f. 13 to 28; 

 Gray, Med. Rep., 1821, p. 239 ; Alder, Mag. Zool. and Bot., 



II, p. 108; Turton, Man., p. 58, f. 42; Jeffreys, Linn, Tr., 



