MANZONIA ZETLANDIOA. 023 



1886. Eissoa (Ah-ania) zetlandicn, DoWhis et Daiitzeuberg, Feuille des Jeunes Natur., vol. xvi, p. l.'M*. 



1895. Bissoia (Flemingia) zetlandica, Sacco, Moll. Terr. Terz. Piem., pi. xviii, p. 30. 



1901. Alvania zetlandica, Brp'gger, Norges geol. Undersjz^gelse, no. 31, pp. 405, 660. 



1901. Manzonia zetlandica, Couch. Soc. List, Joiiru. of Couch., vol. x, p. 18, no. 344. 



1904. Eissoa (Flemingia) zetlandica, CeruUi-Irelli, Palaeout. Ital., vol. xx, p. 194, pi. xv, figs. 48, 49. 



1912, Bissoa zetlandica, Tesch, Med. v. d. Kijks. v. Delfstoffen, No. 4, p. 68, no. 155. 



Specific Characters. — Shell small, oval, turi-eted, strong and solid ; whorls 5 or 6, 

 convex, tuniid, angulated above; coarsely sculptured with strong longitudinal 

 ribs,' which do not quite reach the base of the shell but are cut off in the body- 

 whorl by a distinct spiral keel and decussated by prominent spiral ridges ; between 

 the latter and the mouth there is a rather deep depression ; labial rib thick 

 and prominent; suture deep and channelled; mouth subcircular, expanding 

 somewhat outwards ; outer and inner lips forming a continuous and slightly 

 elevated rim. 



Dimensions. — L. 4 mm. B. 3 mm. 



DistrihiUion. — Recent : British seas from Guernsey to the Shetlands, principally 

 western, sparingly found in the coralline and deep-sea zones. Lofoten Islands, 

 Norwegian coasts, south of Sweden. Cherbourg, Vigo Bay, Mediterranean. 



Fossil: Coralline Crag: Sutton. Waltonian : Walton-on-Naze, 

 Little Oakley. Newbournian : Sutton, Waldringfield. Butleyan : Butley. Pleisto- 

 cene : rirth of Forth. Holocene : Portrush. 



Miocene : Toui-aine, Vienna basin. 



Lower Pliocene : Piacenziano — Zinola, Bordighera, Siena, Normandy. 



Upper Pliocene : Messina, Altavilla, Bologna, Monte Mario. 



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



Isoca,rdia- and Tapes-hanks, Christiania fioi'd. 



Remarks. — This very distinct form has been grouped by some writers with 

 Alvania. In 1884 Jeffreys proposed for it the subgeneric name of Flemingia, but 

 this was superseded in 1870 by the Conchological Society of Glreat Britain, as 

 well as by M. Dautzenberg and others on grounds of priority by Manzonia, 

 a name which it seems likely will be adopted for it in future. M. zetlandica 

 has a wide range in time and space, having been reported from the Miocene of 

 France and Vienna as well as from the Pliocene and Pleistocene of the Mediter- 

 ranean area, where it is still found living. Prof. Br^gger gives it also from the 

 post-glacial beds of Christiania. 



It is not very common in the Crag, though it has been found sparingly from 

 the Coralline to the Butleyan zone. It is specially characterised by its coarse and 

 vigorous sculpture and its angulated whorls. It has been figured in most of our 

 works of reference. 



Specimens from the Crag of Oakley have a more slender and elongated spire 

 and a deeper suture than those from Portrush. 



