TRIGONOSTOMA AMPULLACEUM. 390 



rounded and depressed, not squarely angulate above — as in unworn examples of 

 the latter from the Italian Pliocene {cf. fig. 15) ; moreover, the ribs end in an 

 angulated row of short spines below the suture ; the outer lip, which is grooved 

 within, is gently rounded above and does not forma right angle at the upper corner 

 of the mouth as in 8. LajonJcairei. 



Dimensions. — L. 18 mm. B. 8 mm. 



Distribution. — Not known living. 



Fossil: Coralline Crag : Gomer. Newbournian : Waldringfield, 

 Felixstow. 



Scaldisien : Belgium. 



Miocene: north Germany, Vienna basin, Belgium (?). 



Lower Pliocene : Biot, Piedmont, Ligurian coast, Tuscany. 



Upper Pliocene : Bologna, Asti (abundant), Livorno, Altavilla. 



Remarks. — The fossil from Waldringfield now described, belonging to the 

 Ipswich Museum, agrees very closely with some I obtained at Asti, one of which I 

 have figured with it. It seems to represent Prof. Sacco's variety simplicior. The 

 same type occurs also in the Scaldisien of Antwerp, all of them differing from 

 S. LajonJcairei. M. Van den Broeck reports G. varicosa, Brocchi (G. scalaroides, 

 S. V. W.) from the Belgian Miocene, but to which of the two allied species given 

 above he refers I am unable to ascertain. 8. varicosa is a smaller species than 

 S. LajonJcairei and not so strong and solid. 



Genus TRIGONOSTOMA, Blainville, 1826. 



Trigonostoma ampullaceum (Brocchi). Plate XL, fig. 1. 



1814. Voluta cmpullacea, Brocchi, Conch, foss. subap., vol. ii, p. 313, pi. iii, fig. 9. 



1826. Cancellaria ampullacea, Eisso, Hist. nat. Eur. mc'rid., vol. iv, p. 188, no. 482. 



1841. Cancellaria ampullacea, Bellardi, Desc. Cauc. foss. Piem., p. 35, pi. iv, figs. 7, 8. 



1856. Cancellaria ampullacea, Homes, Foss. Moll. Tert. Wien, vol. i, p. 321, pi. xxxv, fig. 4. 



1872. Cancellaria ampullacea, d'Ancona, Mem. Cart. Geol. Ital., vol. ii, p. 211, pi. xiii, figs. 11, 12. 



1874. Cancellaria ampullacea, Van den Broeck, Ann. Soc. Roy. Malac. Belg., vol. ix, pp. 120, 135. 



1876. Cancellaria ampullacea, Seguenza, Boll. R. Com. G-eol. Ital., vol. vii, p. 8, no. 448. 



1890-4. Cancellaria ampullacea and vars., Sacco, Boll. Soc. G-eol. Ital., vol. ix, p. 263, no. 3838, 1890 ; 



C. (Trigonostoma) ampullaceum and vars., Moll. Terr. Terz. Piern., pt. xvi, p. 9, pi. i, figs. 16 — 20, 



1894. 

 1899. Trigonostoma ampullacea, Cossmanu, Ess. Palcoconch. compar., vol. iii. p. 26. 



Specific Characters. — Shell ventricose, umbilicate ; whorls 5, squarely angulate 

 above, the last much the largest, four-fifths the total length; ornamented by strong, 

 oblique, irregular and sinuous ribs, and by fine, closely-set spiral ridges ; spire 

 short, turreted, rapidly diminishing in size towards the apex, with a wide concave 

 shelf below the suture which is crossed obliquely by the ribs ; suture deep ; mouth 



52 



