Class GASTEROPODA. 



Order PULMONATA. 

 Family HELICIDJE. 



Genus HELIX, Linnajus {em. Miiller). 



[Linn. Syst. Nat. ed. 10, 1758, p. 768; Miiller, Verm. Terr. Fluy. vol. ii. 

 1774, p. 12.] 



Several recent writers have referred to H. pomatia, Linnaeus, 

 as the type of Helix ; there seems to be no reason, however, 

 for departing from the emendation of Miiller, as recognized by 

 authors such as Pfeiffer,' who made an exhaustive study of the 

 genus. 



Type. — Helix lampas, Miiller. 



Helix tasmaniensis, 6. B. Sowerby. 



1845. Helix tasmaniensis, G. B. Sowerby, in Strzelecki, Phys. Desc. 



X.S.W. p. 298, pi. six. fig. 5. 

 1878. Helix tasmaniensis, K. Etheridge, jun.. Cat. Aust. Foss. p. 178. 

 1880. Eelix tasmaniensis, Johnston, Pap. Roy. Soc. Tas. 1879, p. 88. 

 1888. Helix tasmaniensis, Johnston, Geol. Tasmania, pi. xxxiv. fig. 9. 



The description by Sowerby being based on very imperfect 

 materials, the following amplification may be quoted: — "Shell 

 thin, globosely conical, umbilicated ; whorls 4h, rapidly increasing, 

 oniamented with fine obliquely-arcuate striaj, crossed by fine spiral 

 lines . . . , flatly convex above, convex below, last whorl 

 tumid and slightly descending in front ; suture somewhat im- 

 pressed, spire depressly conical ; umbilicus deep, narrow, scarcely 

 one-sixth of the diameter ; aperture oblique, ovately lunate ; 



' Monog. Helic. Viv. 1«18, p. xv. 



