COEBULIB^. 91 



Nesera rostratissima, Edwards (MS.). ' 



Horizon and Localities. 



Lower 'Eocene.— London Clay. Potter's Bar ; Sheppey ; Primrose Hill ; 

 Belsize Lane. 



Nesera serrata, Edwards (MS.). 



Horizon and Locality. 



Upper Eoceue. — Barton Beds. Barton. 



Nesera triradiata, Edwards (MS.). 



Horizon and Locality. 



Lower Eocene. — London Clay. Haverstock Hill. 



Genus ERODONA (Daudin, MS.), Bosc, 1802. 

 Hist. Nat. Coq. 1802, vol. ii. pi. 0. fig. 1, p. 329. 



Potamomya, G. B. Sowerby, 1839. 

 Conch. Man. 1839, p. 88; ed. 2, 1842, figs. 498, 499, p. 236. 



Erodona sequalis, Edwards (MS.). 



Horizon and Locality. 

 Oligocene. — Headon Beds. Ileadon Hill. 



Erodona gregaria, J. Sowerby, 1822. 



Myu yreyaria. 



Mineral Conchology, 1822, pi. 363. (Sowerby Coll.) 



Potamomya yreyaria. 



Mineral Conchology, 1840, vol. vii. (Index), p. 8. 



Horizon and Localities. 

 Oligocene. — Headon Beds. Headon Hill ; Hordwell. 



Erodona plana, J. Sowerby, 1814. 



Mya plana. 

 Mineral Conchology, 1814, pi. 76. fig. 2. (Sowerby Coll.) 



Mya subanyulata. 

 Mineral Conchology, 1814, pi. 76. fig. 3. (Sowerby Coll.) 



Potmnomya plana. 



Mineral Conchology, 1840, vol. vii. (Index), p. 8. 



Horizons and Localities. 



Oligocene. — Headon Beds. Headon Hill ; Hordwell. 

 Upper Eocene. — Barton Beds. Barton. 



Erodona subquadrata, Edwards (MS.). 



Horizon and Locality. 

 Oligocene. — Bembridge Beds. Hempstead. 



