POTERIOCERAS FUSIFORME. 43 



determine in these cases whether such features are of sufficient importance to 

 entitle their possessor to be treated as an independent species, or, on the other 

 hand, whether it should be merged in one already established. Any future 

 attempt to determine with more certainty the affinities of E. Bailyi must depend 

 upon fresh evidence ; as the matter at present stands it is preferable to retain de 

 Koninck's name for this fossil. 



Locality. — Samphire Island, county of Kerry. 



Family Poterioceratid^. 



Genus Poterioceras, M'Coy, 1844. 



Poterioceras FUSIFORME, J. de C. Sowerby, sp. Plate XV. 



1829. Orthocera fusiform is, /. de C. Sowerby. Min. Conch., vol. vi, p. 167, 



pi. dlxxxviii, fig. 1 (excl. fig. 2). 

 1836. Orthoceras fusiforme, Phillips. Geol. of Yorkshire, pt. 2, p. 238, 



pi. xxi, figs. 14, 15. 

 1844. Poterioceras fusiforme, M'Coy. Synop. Carb. Foss. Irelaud, p. 10. 

 1841. Apioceras fusiforme, Fahrenkohl . Bull. Soc. Imp. Nat. Moscou, vol. 



xvii, p. 781. 



1854. Orthoceras fusiforme, Haughton. Journ. Geol. Soc. Dublin, vol. vi, 



p. 48, pi, — , fig. 4. 



1855. — (Poterioceras) fusiforme, M'Coy. Brit. Pal. Foss., fasc. 



iii, p. 569. 

 1862. Poterioceras fusiforme, Griffith. Jouru. Geo). Soc. Dublin, vol. ix, 



p. 55. 

 1876. — — Armstrong, Young, and Robertson. Catalogue 



of the Western Scottish Fossils, p. 59. 

 ? 1880. Gomphoceras fusiforme, L. G. de Koninck. Faune Calc. Carb. Belg., 



torn, v, p. 42, pi. xxxvii, figs. 4 a — c. 

 1888. Poterioceras fusiforme, A. H. Foord. Cat. Foss. Ceph. British Museum, 



pt. 1, p. 259. 



Description. — Shell of medium size, fusiform, gradually expanding, and then 

 contracting towards the aperture, curved in the apical region, straight above ; 

 flattened on the ventral or outer curvature, conspicuously inflated on the dorsal 

 side (PI. XV, fig. 1 c). The apical part slender and tapering to a fine point. 

 Upper part of body-chamber contracted in the region of the aperture, which is 

 simple as in Gyrtoceras. Septa and base of body-chamber markedly oblique at 

 the sides, the septa nearly horizontal in the siphuncular region, strongly arching 

 upwards along the median line of the dorsal region (PI. XV, figs. 1 a, 1 c). Septa 



