PTJLMONATA. LIMN^IB^. 283 



Planorbis obtusus, J. Sowerby, 1815. 



Planorbis ubtimis. 

 Mineral Coacliology, 1815, pi. 140. fig. 3. (Sowerby Coll.) 

 Mon. Pal. Soc. 18.52, pi. xy. figs. I'-l", p. 102. (F. E. Edward.s Coll.) 

 Desc. Anim. sans Vert. 1803, vol. ii. pi. xlvii. figs. 14-17, p. 743. 



Planorbis ambiffuus. 

 Desc. Anim. sans Vert. 18C3, vol. ii. pi. xlvii. figs. 10-13, p. 744. 

 Land- u. Siissw.-Oonch. 1873, pi. xiv. fig. 12, p. 256. 



Planorbis ohtusiis. 



Land- u. Siissw.-Conch. 1873, pi. xv. fig. 2.'i, p. 274. 



Segmentina obtusa. 

 Ann. Soc. R. JIal. Belgique, 1889, vol. xxiv. p. 338. 



Horizotis and Localities. 

 Oligocene. — Heynpstead Beds. Hempstead. — Bembridge Beds. Sconce ; 

 Bembridge. — Ileadon Beds. Ileadonllill: Ilordwell. 



Planorbis oligyratus, Edward.s, 1852. 



Planorbis oliyyratus. 

 Mon. Pal. Soc. 18.52, pi. xv. figs. 3«-3'', p. 103. (F. E. Edwards Coll.) 



Helisotna olij/yraius. 

 Land- u. Sussw.-Concli, 187.3, pi. xvi. fig. 5, p. 286. 



Horizcms and Localities. 

 Oligocene. — Hempstead Beds. Hempstead. — Bembridge Beds. Sconce; 

 Bembridge. 



Planorbis platystoma, Edwards, 1852. 



Planorbis platystoma. 



Mon. Pal. Soc. 1852, pi. xv. figs. 2»-2i, p. 103. (F. E. Edwards Coll.) 



Helisoma platystoma. 



Land- u. Siissw.-Conch. 187-3, pi. xv. fig. 26, p. 276. 

 Horizons and Localities. 



f)lig(icene. — Hempstead Bedn. Hempstead.— /fearfow Beds. Headon Hill ; 

 Colwell Bay; Ilordwt-ll. 



Planorbis Sowerbyl, H. G. lironn, 18.38. 

 Planorbis Sotverbyi. 



Lethsea Geognostica, 1838, vol. 2. pi. xl. fig.s. ]7''-17% p. 1011 

 Mon. Pal. Soc. 1852, pi. xv. Hgs. 0'-9", p. 108. (F. E. Julwards Coll.) 

 Horizon and Localities. 



Oligocene.— /fcarfo?) Beds. Headon Hill ; Ilordwell. 



Planorbis tropis, Edwards, 18.52. 

 Planorbis tropis. 



Mon. Pal. See. 1852, pi. xv. figs. ]0"-10'', p. 106. (F. E. Edwards Coll.) 

 Anisus tropis. 



Ann. Soc. K. Mai. Belgique, 1880, vol. xxiv. pi. xii. figs, 40-48, p. .3.37. 

 Horizon and Locality. 



Oligocene. — Headon Beds. Ilordwell. 



