NATICA (LUNATIA) TENUISTRIATA. 691 



Distribution. — Recent : British coasts, mostly northern. Abroad from Finmark 

 to the Mediterranean. 



Fossil : St. Erth ? Butleyan Crag : Butley. 



Pleistocene : Bridlington, Portland, Bute and Lewis, Clyde beds, Ballyrudder. 



Holocene : Port-rush. 



Upper Pliocene : Sicily — Messina. 



Pleistocene : Castroreale, Messina, Reggio, Ficarazzi, Monte Pellegrino. 

 Topes-banks — Christiania fiord. 



Remarks. — N. Montagui (N. MontcTcuti, Jeffreys, 1 ) is almost unknown from the 

 Crag, but Mr. Bell has reported it from Butley, from the Antrim clays and some 

 other British Pleistocene deposits. Possibly being a small shell it may have been 

 overlooked. As I have not a fossil available I figure a recent specimen from 

 Bergen for the guidance of collectors. Although mainly a northern species it has 

 been recorded as recent from a few southern localities and as a fossil by Seguenza 

 from the Upper Pliocene and Pleistocene of Sicily. Mr. Bell gives it, with some 

 doubt, from St. Erth. 



Natica (Luiratia) tenuistriata (Dautzenberg and Fischer). Plate LIV, figs. 11, 12. 



1848. Natica gmnlandica, S. V. Wood, Mon. Crag Moll., pt. i, p. 146, pi. xii, fig. 5. 

 1911. Lunatia tenuistriata, Dautzenberg et Fischer, Journ. de Conch., vol. lix, p. 26, pi. i, figs. 1 — 3. 

 1913 — 15. Lunatia tenuistriata, Odhner, K. Svenslc. Vet.-Akad. Handl., vol. 1, pt. v, p. 40, pi. iv, 

 figs. 9-15 ; pi. v, fig. 19, 1913 ; vol. liv, pt. i, p. 160, 1915. 



Specific Characters. — Shell fairly strong, smooth, glossy, globose ; whorls 5, 

 finely striated, the last much the largest ; spire short, depressed ; umbilicus rather 

 small, deep, open ; mouth ovate ; outer lip forming an obtuse angle with the body- 

 whorl when viewed from above ; inner lip but slightly spreading. 



Dimensions. — L. 20—26 mm. B. 17 — 21 mm. 



Distribution. — Recent: Nova Zembla, Iceland, Spitsbergen, North of Siberia, 

 Kola Peninsula, Behring Sea. 



Fossil : Pleistocene : Bridlington. 



Remarks. — My friend Dr. Odhner has called my attention to the Bridlington 

 fossil described by Wood in 184S which he thought might be the arctic species 

 Lunatia tenuistriata. By the courtesy of the Curator of the York Museum I have 

 been able to compare Wood's original shell with a recent specimen of that species 

 from the Swedish Riks-Museum, confirming Dr. Odhner's suggestion ; the two 

 correspond accurately, except that the latter is somewhat the larger. The 

 characteristic feature of this species is that the outer lip joins the body-whorl at a 

 different angle to that usual in this group of shells, as shown in my figures (lLc 

 and 12/). 



1 ' Brit. Conch.,' vol. iv, p. 227. 



