78 CRETACEOUS LAMELLIBRANCHIA. 



and Roux, the species now under consideration must be known as Gervillia sub- 

 Ian ceolata (d'Orbigny). 



The young individuals of G. sublanceolata differ from the adults in that the 

 anterior part of the shell is relatively longer and more wing-like, the posterior ear 

 is more sharply limited and its growth-lines are concave posteriorly, and the valves 

 are more unequal (Plate X, figs. 14, 15). 



G. sublanceolata belongs to Freeh's ' Group of G. aviculoides.' Freeh gives a 

 figure of the hinge and interior of a specimen from Atherfield. 



I am greatly indebted to Professor Douville for the opportunity of seeing a 

 specimen of Gervillia anceps from Aube, and also for his kindness in comparing G. 

 sublanceolata with the specimens of G. anceps in the Ecole des Mines, Paris. 



Types. — One of the specimens figured by Sowerby (fig. 5) is in the British 

 Museum ; the others (figs. 1 — 3) cannot be traced. Sowerby's fig. 4 is from the 

 Corallian of Shotover, and does not belong to this species. Avicula lanceolata, 

 Forbes, from the Lower Greensand (probably Crackers) of Atherfield, is in the 

 Museum of the Geological Society (No. 2057). The type of Gervillia alpha came 

 from the Gault of Saxonet. 



Distribution. — Lower Greensand (Crackers and Fitton's Beds 20 and 45) of 

 Atherfield. Atherfield Beds of Sevenoaks. 



Recorded by Topley from the Atherfield Beds of Haslemere, Peasmarsh, Shal- 

 ford, and Redhill ; from the Hythe Beds of Hythe, Lympne, Maidstone, and 

 Pulborough ; and from the Sandgate Beds of Sandgate, Folkestone, and Parham. 



Upper Greensand (zone of Schloenbackia rostrata) of the Isle of Wight, Black- 

 down, and Haldon. 



Gervillia linguloides, Forbes, 1845. Plate XI, figs. 2-8. 



1845. Gervillia linguloides, E. Forbes. Quart. Journ. Geol. Soc, vol. i, p. 246, 



pi. iii, fig. 9. 

 Avicula ephemera, Forbes. Ibid., p. 247, pi. iii, fig. 6. 



1846. Gervillia linguloides, A. d'Orbigny. Pal. Franc. Terr. Oct., vol. iii, p. 



485, pi. cccxcvi, figs. 1 — 4. 

 1850. d'Orbigny. Prodr. de Pal., vol. ii, p. 119. 



Avicula ephemera, Ibid., p. 119. 



1854. Gervillia linguloides, J. Morris. Cat. Brit. Foss., ed. 2, p. 167. 



— Avicula ephemera, Morris. Ibid., p. 163. 

 1858. Gervillia linguloides, F. J. Pictet and E. Benevier. Foss. Terr. Aptien 



(Mater. Pal. Suisse, ser. 1), 

 p. 123, pi. xviii, figs. 3, 4. 

 1869. F. J. Pictet and G. Campiehe. Foss. Terr. Cret. Ste. 



Croix (Mater. Pal. Suisse, 

 ser. 5), p. 91. 



