0PI8TH0EEANCHIATA. BTJILIDiE. 267 



BuUa uniplicata. 

 Dixon's ' Sussex,' 1850, pi. vii. fig. 8, p. 177. (F. E. Edwards CoU.) 



Cylichna Brugu&ri. 

 Desc. Anim. sans Vert. 1863, vol. ii. p. 632. 

 Ann. See. K. Mai. Belgique, 1889, vol. xxiv. p. 312. 



Horizons and Localities. 

 Middle Eocene. — Bracklesham Beds. Braoklesham Bay ; Stubbington. 

 Lower Eocene. — London Clay. Clarendon. 



Genus ACERA, 0. F. Miiller, 1776, em. Lamarck, 1822. 



Akera, O. F. Muller, 1776. 

 Zool. Danicse Prod. 1776, vol. 2. p. 88. 



Acera, Lamarck, 1822. 

 Hist. Nat. Anim. sans Vert. 1822, vol. 6. part 2, p. 28. 



Acera striatella, Lamarck, 1804 and 1806. 



Bulla striatella. 

 Ann. Mus. 1804, vol. 4. p. 221 ; 1806, vol. 8. pi. xi. fig. 3. 



Bulla striatella. 

 Coq. Fobs. Paris, 1824, vol. ii. pi. v. figs. 7-9, p. 43. 



BtUlaJUosa. 

 Mineral Oonchology, 1824, pi. 464. fig. 4. (Sowerby Coll.) 



Akera striatella. 



Desc. Anim. sans Vert. 1863, vol. ii. p. 640. 



Acera striatella. 



Ann. Soc. R. Mai. Belgique, 1889, vol. xxiv. p. 318. 

 Horizon and Localities. 



Upper Eocene.— Barton Beds. Barton; High Cliff; Alum Bay (no, 29 

 Bed). 



Genus ATYS, Montfort, 1810. 

 Conch. Syst. 1810, vol. 2. p. 343. 



Atys aperta, Edwards (MS.). 

 Horizon and Locality. 

 Middle Eocene. — Bracklesham Beds. Bracklesham Bay. 



Atys biumbilicata ?, Deshayes, 1863. 

 Haminea biumbilicata. 

 Desc. Anim. sans Vert. 186.3, vol. ii. pi. xxxix. figs. 33-35, p. 640. 



Atys biumbilicata. 



Ann. Soc. R. Mai. Belgique, 1889, vol. xxiv. p. 316. 

 Horizon and Locality. 



Middle Eocene.— Bracklesham Beds. Bracklesham Bav. 



