FAMILY COLIMACEA. 121 



Hob. Northern and Central Europe. Throughout England, but chiefly 

 in the southern and eastern counties, local and rare. More rare in Ire- 

 land. (In woods, among wet moss or under stones.) 



It was the peculiarity of the sinistral or left-handed convolution 

 of this species that induced the eminent Danish naturalist of the 

 last century, Muller, to establish his genus Vertigo. It has a stoutly 

 cylindrical moderately glossy shell, smooth, or only very faintly 

 striated, with a triangularly ovate aperture, armed with at least sis 

 to seven solid teeth. The animal is of a dusky grey-slate colour, 

 pale towards the sides, with a pair of widely diverging tentacles ; 

 and according to Forbes and Hanley it has a pair of almost obsolete 

 lower tentacles. This observation has not, however, been confirmed 

 by Moquin-Tandon. 



V. pusilla is found in several parts of England, local and rare, 

 and still more rare in the north and west of Ireland. On the Con- 

 tinent it ranges from Sweden to Switzerland and Lombardy. 



7. Vertigo vertigo. Reversed Vertigo. 



Shell ; minute, sinistral, ovately cylindrical, attenuately contracted 



at thebase, scarcely umbilicated, fuscous horny, 



semitransparent, glossy, whorls four to five, 



tumidly convex, obliquely rather strongly 



striated, constricted at the sutures ; aperture 



small, compressly ovate, with four to five 



teeth, two of which are on the body-whorl, 



and only one on the opposite margin, lip 



rather thickened, but little reflected. 

 Turbo vertigo, Montagu (1803), Test. Brit. p. 363. pi. 



xii. f. 6. 

 Vertigo Venetzii, Charpentier (1822), Feruss. Tail. Syst. p. 65 (without 



characters). 

 Vertigo angustior, Jeffreys (1830), Trans. Linn. Soe. 1830, vol. xvi. p. 361. 

 Vertigo nana, Michaud (1831), Comp. de Drap. p. 71. pi. xv. f. 24, 25. 

 Vertigo Tiamata, Held (1837), Isis, p. 304. 



Vertigo plicata, August Muller (1838), Weigm. Arch. p. 210. pi. iv. f. 6. 

 Pupa nana, Deshayes (1838), Anim. sans vert. vol. viii. p. 190. 

 Pupa ( Vertigo) Venetzii, Pfeiffer (1848), Monog. Helic. Vic. vol. ii. p. 364. 

 Vertigo (Vertilla) plicata, Moquin-Tandon (1855), Hist. Moll. vol. ii. p. 



408, pi. xxix. f. 8 to 11. 



