Nigerian Eocene Mollusca. 59 



of Crepidula may be made, although there are no species exhibiting very close 

 affinities with the Nigerian shell. There is Mayer-Eymar's Crepidula indigena 

 (Journ. Conchyl., 1903, pi. 13, fig. i, p. 318) from the Lutetian of Egypt, which 

 was founded on a natural cast, but being without internal characters it might just 

 as well belong to Capulus as Crepidula, or even Hipponyx as suggested by 

 Oppenheim (Palaeontographica, 1906, Vol. 30, part 3, pi. 22, figs. 36, 37, pp. 261, 

 262). The only Crepidula mentioned by M. Cossmann (Ann. Soc. R. Mai. 

 Belgique, 1888, Vol. 23, p. 192, pi. 7, figs. 29-31) from the Parisian Eocenes is 

 his C. parisiensis, an extremely small shell and without any observant muscular 

 impressions. More resemblances, perhaps, may be observed with Conrad's 

 Crepidula lirata from the Alabama Eocene (see de Gregorio : Ann. Geol. 

 Paleont., 1890, part 7, pi. 13, figs. 49-58, p. 146), although the diaphragm in that 

 species occupies a greater area of the aperture, while the sculpture includes 

 numerous radial costae, the Nigerian shell being more or less polished and 

 smooth, the obscure radial striations being almost obsolete. The new species is 

 named after Dr. J. D. Falconer, Director of the Geological Survey of 

 Nigeria. 



OCCURRENCE. Cuttings Nos. i, 5, 6, 10, n, 12, 13, 14, 15. 

 COLLECTOR. Mr. Kitson. 



Family 

 Calyptraea crepidularis (Lamarck). 



PLATE 4, figs. 18, 19. 

 Calyptraea crepidularis. 



Lamarck: Ann. Mus. (Paris), 1802, Vol. i, p. 385; Deshayes : Desc. Coq. Foss., Paris, 1824, Vol. 

 2, p. 32, pi. 4, figs. 16-18 ; Cossmann : Ann. Soc. R. Mai. Belgique, 1888, Vol. 23, p. 194. 



REMARKS. This species is interesting as occupying a more or less 

 intermediate position between Calyptraea and Crepidula ; following M. 

 Cossmann at the present day, it is here regarded under the first named 

 genus. The original description is as follows : " Testa subovata, convexo- 

 gibbosa, obsolete echinata ; spira submarginali." Deshayes first referred to it 

 as related to both Calyptraea and Crepidula, a view since supported by M. 

 Cossmann. The Nigerian shell exhibits a similar sunken septum as is 

 present in the European form, being besides prominently umbilicated at the 



