BIVALVIA. 27 



P. 'Groenlandicus, Loven and G. B. Sow., Thes. Conch., p. 57, PI. 13, fig. 40, 

 appears to differ from our shell only in being somewhat larger. 



4. Pecten tigrinus, Mutter. Tab. V, fig. 2, a—g. 



P.ECTEN TIGKINUS. Miill. Zool. Dan., ii, p. 26, pi. 60, figs. 6—8, 1776. 



— Besh. 2d ed. Lam., t. viii. p. 155, 1835. 



_ _ Nyst. Coq. Foss. de Beige, p. 303, pi. 23, figs. 4—10, 1844. 



_ — Loven. Ind. Moll. Scand., p. 31, 1846. 



_ — ^Wer. Cat. of Moll. North, and Durh., p. 77, 1847. 



_ _ Forb. and Hani. Hist, of Brit. MoU., vol. ii, p. 285, pi. 50, figs. 8—11. 



— OBSOLETUS. Penn. Brit. Zool., vol. iv, p. 322, t. 64, fig. 3. 



_ — Bon. Brit. SheUs, vol. i, t. i, fig. 2, 1799. 



_ Mont. Test. Brit., p. 149, and sup., p. 57, 1808. 



_ — Turt. Brit. Biv., p. 213, pi. 9, fig. 6, 1822. 



_ _ Brown. lUust. Conch. Gr. Brit., pi. 33, fig. 6, 1827. 



_ — /. Sowerby. Min. Conch, t. 541, figs. 1—8, 1828. 



_ _ Nyst. Rech. Coq. Foss. d'Anv., p. 19, No. 74, 1835. 



_ _ S. Wood. Catalogue, 1840. 



— — J. Morris. Cat. of Brit. Foss., p. 115, 1843. 

 _ _ Thorpe. Brit. Mar. Conch., p. 118, 1844. 

 PARVUS. Ba Costa. Brit. Conch., p. 155, 1778. 



— L^vis. Penn. Brit. Zool., vol. iv, p. 102. 



_ — Mont. Test. Brit., pp. 150, 579, pi. 4, fig. 1, 1803. 



_ — Turt. Brit. Biv., p. 212, 1822. 



_ — Brown. Illust. Conch. Gr. Brit., pi. 33, fig. 7, 1827. 

 _ DOMESTicus. Chem. Conch. Cab., t. xi, p. 261, pi. 207, figs. 2030-2036, 1783. 

 OsTBEA OBSOLETA. Turt. edit. Linn., vol. iv, p. 266, 1806. 

 _ _ JF. Wood. Ind. Test., p. 50, pi. 10, fig. 37. 

 — Mawe. Linn. Conch., pi. 14, fig. 6. 



— TiGEEiNA. Turt. edit. Linn., vol. iv, p. 268, 1806. 



— L.EVis. Mat. and Rack. Linn. Trans., vol. viii, p. 100, pi. 3, fig. 5, 1807. 

 _ _ >F. Wood. Ind. Test., pi. 10, fig. 38. 



Spec. Char. Testa (Bquivalvi, cBquilaterali, siiborhiculari ; radiatd, radiis varus,^ 

 mterdmi obsoletis, striis suhtilissimis arcuatim diver gentihus ornatd; auriculis valdi 



incecjualibus. 



Shell equivalve, equilateral, suborbicular ; costated costse variable, sometimes 

 obsolete, or small and numerous, sometimes arranged in fives ; ornamented with fine 

 curved and diverging striae, ears very unequal. 

 Diameter, 1 inch. 



Locality. Cor. Crag, Sutton, Ramsholt, Gedgrave, Sudboum. 

 Red Crag, Sutton, Bawdsey, and Walton Naze. 



Recent, Britain and North Seas. 



This is a very abundant species in the Coralline Crag, with as great a range in 



