INVERTEBRATE PALAEONTOLOGY. 549 



accidentally placed there, as nothing of the kind is seen in the third. If 



I his is a natural callus, however, (he species would of course belong lo some 

 widely removed genus from Hyalina. 



Locality and position. — Same as preceding. 



HELICIDiE. 



Genus HELIX, Linnaeus. 



Synon.— Helix, Linu. (1758), Syst' Nat., 768.— Miiller (1774), Hist. Venn., 11,12; and (1776) Zool. Dan. 

 Prodr., xxx and 239.— Brug. (1789), Encyc. M6th., I, xvi— Cuvier (1798), Tab. Elcm., 

 396.— Lam. (1801), Syst. An., 93 (not 1799).— Moutfort (1810), Couch. Syst., II, 230.— 

 H. and A. Adams (1855), Genera of Recent Moll., 11,188; and of numerous other 

 authors, at various dates, and with various limits. 



Pomatia, Bolten (1798), Mus. (ed. 2a, 1819, 52).— Beck (1837), Iud., 43.— Gray (1840), in Tnrton'a 

 Man. (2d ed.), 137.— Albers (1860), Die Heliceen, 140 (as a subgenus under Helix). 



Lucena, Hartm. (1821), in Neues Alp., I, 208 (not Oken 1815). 



Caniareus, Risso (18261, Hist., IV, 64.— Beck (1837), Ind., 44. 



Cwnatoria, Held (1837), in Oken's Isis, 910. 



Galaxias, Beck (1837), Iud., 42.— II. and A. Adams (1855), Genera Recent Moll., II, 189 (as a sub- 

 genus under Helix). 



Camama, Albers (1850), Hel., 85— H. and A. Adams (1855), Genera Recent Moll., II, 189. 



Etym. — f/.if, spiral. 



Exatiip. — Helix pomatia, Linmcus. 



Shell more or less globose or subturbinate, imperforate or umbilicate, 

 the umbilical perforation being sometimes covered in the adult by the expan- 

 sion of the inner lip ; spire depressed or sometimes moderately prominent; 

 volutions convex, the last one being ventricose, and generally deflected at the 

 aperture, which is more or less lunate-suborbicular ; peristome generally 

 thick and reflexed, rarely thin and simple ; columellar margin dilated, and not 

 dentate. 



The above diagnosis and synonymy are intended to include the follow- 

 ing sections : 



1. helix, Linn, (typical). 



Shell more or less nearly globose, imperforate, or with perfora- 

 tion covered ; peristome patulous or reflexed ; columellar margin 

 dilated and callous. — (Type as already cited.) 



2. galaxias, Beck. 



Shell globose, umbilicate; aperture generally shining within; 

 peristome thick, expanded, reflexed, or rarely simple, obtuse with 

 margins approximated, and often united by a callus; columella dilated, 

 and somewhat covering the umbilicus. — (Helix globulus, Miiller.) 



