646 PLIOCENE MOLLUSOA. 



1872. Littorlna Jittorea, A. and R. Bell, Proc. Geol. Assoc, vol. ii, pp. 209, 213, 21fi. 



1878. Littor'nia Jittorea, G. O. Sars, Moll. Reg. arct. Norv., pp. 164, 358. 



1892. Littorlna littorea, Locard, Coq. mar. Cotes de France, p. 189, fig. 165. 



1894. Littorina littorea, Muntlie, Bull. Geol. Inst. Univ. Upsala, vol. ii, p. 2. 



1901. Littorina littorea, Brjigger, Norges geol. Unders0gelse, No. 31, p. 657, pi. ix, fig. 12; pi. xii, 



figs. 6, 8, 10, 11. 

 1908. Littorina littorea, Kobelt, Icon, sclialentrag. europ. Meeresconch., vol. iv, p. 55, pi. ex, figs. 1 — 5. 

 1912. Littorina littorea, Dautzenberg et Fischer, Camp. Scient., Prince de Monaco, vol. xxxvii 



(MoUusques), p. 181. 

 1915. Littorina litorea, Johnson, Bost. Soc. Nat. Hist., Occ. papers, vol. vii. Fauna of New England, 



No. 13, p. 120. 



Specific Characters. — Shell strong and solid, whorls in the type form 

 regularly conical, the last ventricose, much the largest, more convex in the female ; 

 spire short ; apex pointed ; suture indistinct ; mouth angulate above, expanded 

 below ; oiiter lip thickened, with a thin edge ; pillar short, thick, shelving 

 inwards. 



Dimensions. — L. 30 mm. B. 24 mm. 



Distrihntlon. — Recent : British coasts, locally abundant. Norwegian coast from 

 Finraark to Christiania, Lofoten Islands, West European as far south as 

 Gibraltar, Russian Lapland, White Sea, Icy Cape, Greenland, Canada, Newfound- 

 land, New England coasts, Alaska. 



Fossil: Red Crag (rare) — Newbournian : Waldringfield, Ramsholt, 

 Newbourn, Sutton. Butleyan : Bawdsey, Hollesley, Butley. Icenian : jiassim. 

 Isle of Man, Wexford. 



Pleistocene : British Isles, widely diffused. Christiania region from Mya-heds 

 to ?'ajop.?-banks (Br/argger), Trondhjem (0yen). Uddevalla. Baltic — Littorina sea 

 region. 



Remarks. — This well-known littoral species made a late appearance in the 

 Pliocene deposits of the East of England having been found but rarely in the upper 

 part of the Red Crag ; it is more abundant in the Norwich and Weyl^ourne zones of 

 the Icenian, as at Bramerton. It is, however, a characteristic form of the British 

 Pleistocene, but I am not aware that it has been recorded as a fossil from any 

 locality to the south of these islands. Prof. Brjsrgger gives it from the upper zones 

 of the Christiania deposit, and Dr. 0yen from those of Trondhjem. It lived, more- 

 over, at the head of the Gidf of Bothnia (where it does not now exist) during what 

 is known to Scandinavian geologists as the " Litorina-time " — an indication, in their 

 opinion, that the salinity of the water in that region was greater then than it is 

 now. 



As a recent shell the range of L. littorea is mainly to the north and north- 

 west of the British Isles, extending as far in the latter direction as Alaska. It 

 extends to the south also, as stated above, along the Atlantic coasts of Western 

 Europe to the straits of Gibraltar, though not abundantly. 



