MANGILIA COSTATA. 245 



Pleistocene : Ireland — Belfast, Portrusli ; Scotland — Cumbrae, Largo Bay. 



Scaldisien, Poederlien : Belgium. Scaldisien : Holland. 



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



Pleistocene : Livorno, Ficarazzi, Monte Pellegrino. 



The generic name Mavgilia} (formerly Mangelia) is now ui^ed for a group of 

 small inoperculate Pleurotomidae, longitudinally costated, with a thickened or 

 varicose outer lip, a narrow mouth, a well-marked sinus, and a short canal. 



Reinorks. — The type form of this well-known British shell is fairly common in 

 the Coralline, and not very rare in the Red Crag, as at Oakley, where, however, it 

 is not nearly so abundant as llapJtifoma mitrula. It seems to be the southern 

 variety of the present species ; the variety coarctata, described below, lieing more 

 characteristic of northern regions. 



Var. coarctata (Forbes). Plate XXIX, fig. 14. 



1840. Pleurotoma coarctata, Forbes, Mag. Nat. Hist., vol. v, p. 107, pi. ii, fig. 15. 



1853. Mangelia costata, var. coarctata, Forbes and Hanley, Brit. Moll., vol. iii, p. 486, pi. cxiv a, 



fig. 5. 

 1867. Pleurotoma costata, var. coarctata, Jeffreys, Brit. Concli., vol. iv, p. 380. 

 1901. Mangilia costata, var. coarctata, Br0gger, Norges geol. uuders0gelse, vol. xxxi, p. 662, pi. xviii, 



fig. 19. 

 1905. Mangilia costata coarctata, Kobelt, Icon, sclialentrag. europ. Meerescoucli., vol. iii, p. 344, 

 • pi. xciv, figs. 21—23. 



1910. Mangilia. costata, var. coarctata, Cerulli-Irelli, Palaeont. Ital., vol. xvi, p. 54, pi. v, fig. 12. 

 1914. Mangilia costata, var. coarctata, Cipolla, Palaeont. Ital, vol. xx, p. 142, pi. xiii, fig. 11. 



Varietal Characters. — More slender than the type ; spire elongate ; mouth 

 narrow, lanceolate. 



Dimensions. — L. 10 — 12 mm. B. o mm. 



Distribution. — Recent : British and Scandinavian seas. Palermo (Monterosato). 

 Fossil, : Waltonian Crag : Walton-on-Naze, Beaumont, Little 

 Oakley. Butleyan : Butley ; no doubt elsewhere in the Red Crag. St. Erth. 



Upper Pliocene : Monte Mario, Altavilla. 



Pleistocene : Isocardia- and Tapes-banks of Christiania and Trondhjem (0yen) ; 

 Ficarazzi. 



Remarls. — This Avell-known variety, originally described by Forbes as specific- 

 ally distinct, seems, as just stated, to be characteristic of northern seas, the type 

 having generally a more southern range. The Marchese di Monterosato, however, 

 has taken it as a Recent shell at Palermo. Prof. Kendall informs me he found the 

 present variety as well as the type form to be rather common at Walton, and I have 

 a fair number of each in my collection from Oakley. Probably some of those 



1 Named after the naturalist Manglli. 



