TRIVIA AVELLANA. 509 



Distribution. — Not known living. 



Fossil : Coralline Crag, Waltonian and Newbournian zones of 

 Red Crag, fairly common in places. 



Re^narJiS.— This, species and its variety angliiv may be distinguished from the 

 typical form of T. enropsea by the smaller number of its transverse ridges, 

 generally about 8 or 9 in number, and by its more globular and rounded form. 

 It is not so abundant in the Crag as is the latter, though fairly common in places. 

 I have obtained 40 specimens or more from Oakley. It is a PHocene species. I 

 have no knowledge of its having been found at any Pleistocene locality. 



Var. anglise, S. V. Wood. Plate XLV, fig. 9. 



1842—48. Trivia angVuv, S. V. Wood, Ann. Mag. Nat. Hist. [1], vol. ix, p. 543, 1842 ; Mon. Crag 



Moll., pt. 1, p. 16, pi. ii, fig. 7, 1848. 

 1871. Cyprxa retusa, var., Jeffreys in Prestwich, Quart. Jovirn. Geol. Soc, vol. xxvii, p, 488. 

 1881. Cypnea retusa, var. anglix, Nyst, Couclt. Terr, tert, Belg., p. 60. 

 1890. Cypreea anglipe, C. Reid, Plioc. Dep. Brit., p. 248. 



Varietal Characters, — Resembles T. retusa in size, form, and the smaller number 

 of its transverse ridges, but may be distinguished from the latter in havino- a 

 well-marked dorsal sulcus. 



Dimensions. — L. 10 mm. B. 8 mm. 



Distribution. — Not recorded living. 



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

 Little Oakley. Newbournian : Waldringfield, Newbourn, Sutton. 



Uemarhs. — This form is rare in the Crag, but it has been reported from the 

 Coralline horizon and from several localities in the Red. I found half a dozen 

 specimens at Oakley, one of which is here figured. By Jeffreys and Nyst it was 

 regarded as a variety of T. retusa, a view which in his Supplement Wood seemed 

 inclined to accept. 



Trivia avellana (J. Sowerby). Plate XLV, fig. 10. 



1823. Cyprasa avellana, J. Sowerby, Min. Conch., vol. iv, p. 107, pi. ccclxxviii, fig. 3. 



1842—48. Trivia avellana, S. V. Wood, Ann. Mag. Nat. Hist. [1], vol. ix, p. 543, 1842; Cyprasa 



avellana, Mon. Crag Moll., pt. i, p. 15, pi. ii, fig. 5, 1848. 

 1843—81. Gypnea avellana, N^st, Coq. foss. Terr. tert. Belg., p. 608, pi. xlv, fig. 13, 1843; Conch. 



Terr. tert. Belg., p. 58, pi. v, fig. 1, 1881. 

 1870—98. Cyprsea avellana, A. Bell, Journ. de Conch., vol. xviii, p. 349, no. 311, 1870 ; Geol. Mag., 



vol. viii, p. 454, 1871 ; Trans. Roy. Geol. Soc. Cornwall, vol. xii, p. 136, 1898. 



1871. Cyprsea avellana, Jeffreys in Prestwich, Quart. Journ. Geol. Soc, vol. xxvii, pp. 143, 488. 



1872. Cyprxa avellana, A. and R. Bell, Proc. Geol. Assoc, vol. ii, pp. 203, 209, 213. 

 1875. Trivia avellana, Dollfus, Ktud. Terr. tert. Cotentiu, vol. vi, p. 367. 



1890. Cypriea avellana, C. Reid, Plioc Dep. Brit., p. 243. 



1892. Cypriea avellana. Van den Broeck, Bull. Soc. Beige Geol., vol. vi (Memoires), pp. 122, 123, 143. 

 1894. Trivia avellana and vars., Sacco, Moll. Terr. Terz. Piem., pt. xv, p. 51, pi. iii, fig. 41 ; T. sphieri- 

 culata, var. propeavellana, p. 49, fig. 35. 



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