BIVALVIA. 231 



Locality. Red Crag, Sutton, Walton Naze. 



Mam. Crag, Bramerton, Postwick, and Chillesford. 



This shell in some parts of the Red Crag is exceedingly abundant, though rare at 

 Walton on the Naze. At Sutton I have frequently found specimens with the valves 

 united and the ligament preserved, strong presumptive evidence of their having lived 

 and died in the locality wherein they were found. 



This species was named by the late Rev. G. R. Leathes, in consequence of its con- 

 nexion or resemblance to T. tenuis, perhaps its nearest relative. It is somewhat in form 

 like T. Balthica, but is not so tumid or thick : it differs from T. tenuis in having more 

 height, with a greater convexity in the ventral margin ; the two teeth in each valve are 

 alternately simple and bifid, the bifid one is anterior in the left valve, and vice versa ; 

 and there are no lateral teeth, but there is a very distinct one on the anterior side in 

 T. tenuis, and in that species the mantle mark is comparatively larger. 



In well-preserved specimens, the surface is covered with fine concentric striae, or 

 lines of growth, more especially upon the posterior slope, and the right valve is the 

 more tumid of the two ; there is also a slight diflference in the magnitude of the 

 palleal sinus in the opposite valves. 



The shell which really makes the nearest approach to this species is one that was 

 brought from the S. E. Coast of Australia. 



7. Tellina Balthica, Linnmis. Tab. XXII, fig. 1, a — c. 



Tellina Balthica. Linn. Syst. Nat., ed. 12, p. 1120, No. 68. 



— — Born. Test. Miis. Ctes. Vinci., p. 38, t. 11, fig. 14, 1780. 



— - Phil. En. MoU. Sic, vol. i, p. 28 ; and vol. 2, p. 22. 



— Baltica. Lyell. Phil. Trans., 1835, p. 34, var. a, pi. 11, figs. 1,2; var. h, 



figs. 3, 4. 



— SOLIDIJLA. Pulteney. In Hutchin's Hist. Dorset, p. 29. 



— — Woodw. Geol. of Norf., pi. 2, fig. 13, 1832. 



— — Lovhi. Ind. Moll. Scand., p. 41, 1846. 



— — Middend. Mai. Ross., loc. cit., p. 577, 1849. 



— KUBKA. Ba Costa. Brit. Conch., p. 211, t. 12, figs. 4, 4, 4. 



— CARNARiA. Penn. Brit. Zool., vol. iv, p. 88, pi. 49, fig. 32. 



— — J.E. Gray. List of Brit. Moll., p. 41, 1851. 



— ZONATA. Gmel. Syst. Nat., p. 3238, No. 52. 



— INCONSPICUA. ? Bi-od. and Sow. Zool. Journ., vol. iv, p. 363, 1829. 



_ _ 9 Gray. Zool. Beechey's Voy., p. 153, t. 41, fig. 6, 1839. 



— Groenlandica. {Beck.) Lyell. Trans. Geol. Soc, vol. vi, 2d series, pi. 16, fig. 8, 



1839. 

 PsAMMOBiA FUSCA. Say. Journ. Acad. Nat. Sc, v, p. 220. 



— SOLIDULA. Turt. Brit. Biv., p. 95, t. 8, fig. 2, 1822, 



Sanguinolaria fdsca. Conrad. Am. Mar. Conch., 34, pi. 7, fig. 1. 



— — Deltay. Nat. Hist. New York (Zoology), pi. 32, fig. 304. 



LiMicoLA CARNARIA. " Leach." Sec. Gray. 



