Nigerian Eocene Mollusca. 85 



Family VENERID^. 

 Cordiopsis incrassata (J. Sowerby). 



PLATE 9, figs. 15-17. 



Venus Meroe. 



Solander : Brander's " Fossilia Hantoniensia," 1766, pi. 8, figs. 104, 105, p. 41, non Linnaeus. 



Venus (Cytherea) incrassata. 



J. Sowerby: Mineral Conchology, 1817, Vol. 2, pi. 155, figs, i, 2, p. 126, non V. incrassata Brocchi, 

 1814. 



Cytherea incrassata. 



Deshayes : Descr. Coq. Foss, Paris, 1825, Vol. i, pi. 22,' figs. 1-3, p. 136. 



Venus incrassata. 



Nyst : Mem. Cour. Acad., Belgique, 1845, Vol. 17, pp. 181, 640 (Belgium). 



CytJterea incrassata. 



Deshayes : Suppl. Descr. Coq. Foss., Paris, 1858, Vol. I, p. 454. 



Meretrix incrassata and bartonensis. 



Edwards (Ms.) : R. B. Newton's Syst. List F. E. Edwards Coll. British Oligocene and Eocene 

 Moll. British Mus., 1891, pp. 63, 64. 



Cytherea incrassata. 



Koenen : Abhandl, geol. specialkarte Preussen, 1894, Vol. 10, part 6, pi. 87, figs. 1-3, p. 1259 

 (Germany) ; Oppenheim : Palaeontographica, 1906, Vol. 30, part 3, pi. 19, fig. 24, p. 173 (Egypt) 



Dosinia (Sinodia) incrassata. 



Jukes-Browne: Proc. Mai. Soc., London, 1908, Vol. 8, pi. 6, fig. 2, pp. 151-154 (British). 



Cordiopsis incrassata. 



Cossmann : Act. Soc. Linn., Bordeaux, 1910, Vol. 64, p. 387 (France). 



REMARKS. Several valves in the collection can be referred to this well 

 known species. The younger or smaller examples (Height = 28, Length = 

 30 mm.) exhibit a globulose and subtrigonal shape whereas the more adult 

 forms (Height = 35, Length = 38 mm.) assume a somewhat oval contour. 

 The small and more or less conical isolated tooth in front of the left valve 

 which fits into a socket of the opposing valve is quite well displayed together 

 with the prominently marked ascending pallial sinus with its obtusely pointed 

 apex. As in European examples the lunule is not excavated although 

 distinctly circumscribed, thus differing from Dosinia in which the lunule is 

 sunken. 



It was first suggested by Nyst that Solander's Venus meroe from the 

 British Barton Beds, which however was not the Linnaen recent shell of the 

 same name, was in all probability the equivalent of Sowerby 's V. incrassata 



