CrKENIDvE. 59 



Cyrena sororcida, Edwards (MS.). 



Horizon and Locality. 



Lower Eocene. — Woohoich Beds. Upnor. 



Cyrena subdepressa, Edwards (MS.). 



Horizon and Locality. 



Ujiper Eocene. — Barton Beds. High Cliff. 



Cyrena subregnlaris, Edwards (MS.). 



Horizon and Localities. 

 Oligocene. — Headon Beds. ColwoUBay; ITeadonHill; ueM Beaulieii Koad. 



Cyrena tellinella, Ferussac and Oeshayes, 1820. 



Cyrena tellinella. 

 Hist. Nat. Moll. 1820, vol. i. p. 22, no. 247 (no description) ; vol. ii. W'^. 1 



(end plate not numbered). 

 Uoq. Foss. Paris, 1824, vol. 1. pi. xix. figs. 18, 19, p. 123. 



Horizon and Localities. 



Lower Eocene. — Woohoich Beds. Upnor; Charlton; Woolwich. 



Cyrena transversa (Forbes, MS.), Morris, 1856. 

 Cyrena transi-ersa. 



Forbes's 'Isle of Wight,' Mem. Geol. Siirv. 18>0, pi. iii. fig. 0, pp. m, 148. 

 Horizon and Locality. 

 Oligocene. — Bembridye Beds. Hempstead. 



Cyrena, sp. 



Horizons and Localities. 

 0[igocene.—Be7nbridffe Beds. Hempstead.— -Hearfon Beds. Lyndhurst; 

 Colwell Bay. 



Genus SPH.aE:RIUM, Scopoli, 1777. 



Introd. Hist. Nat. 1777, p. 397. 



Cyclas, Bruguiere, 1792. 



Tab. Encycl. M^th. 1702, vol. 2 pi. 302. 



Sphserium Bristovii (Forbes, MS.), Morris, 1856. 

 Cyclas Bristoi'ii. 

 Forbes's 'Isle of Wight,' Mem. Geol. Surv. 1860, pi. ii. fig. 3, p. 140. 



Cyclas Iiristovii{?). 



Mon. I'al. Soc. (Supp.), 1877, pi. b. fig. 6, p. 18. 

 Horizmi and Locality. 



Oligocene. — Hempstead Beds. Hempstead. 



Sphseriiun exigunm, S. V. Wood (MS.), 1847. 



Cyclas c.viyua. 

 Lond. Geol. Joum. 1847, no. iii. p. 118. 



