OSTREA. 387 



Ti/pen. — Ostracifes siilcafiift, Blumenbacli, from the Ht-nonian of Salzberg near 

 Quedlinbm-g, is stated by Hcnnig to he in the Natural History Museum, Berlin. 

 Odrea sp. Mantell, from the zone of Micnistcr ror-KiKjiiiiiinn of Sontherham near 

 Lewes, and 0. spmlplann, Sowerby, from the zone of BdomnitelJa mucronnfa of 

 Norwich, are in the British Museum. (>. iil,v/(irniis, Woodward, and 0. iiipqjiicdsfiitit, 

 Woodwaixl, are from the zone of B. iiiiifniiiiitit of Xoi'wieli ; tlie original of fig. 3 of 

 the former is in the Norwich Museum, but the other specimens cannot lie found. 

 0. carinain, Sowerby (in Di.Kon), cannot be found. 



DhtribaUon. — Probably zone of TerehratnJina lala of tlie Suutli JJevon coast. 



Zone of HdJaster plnnvs of the South Devon coast, Froxfield (Hants.), White 

 Hill near Goring, and Hart's Lock Wood. 



Zone of Micrasfer cor-fi'xfii(Uii(irunii of Stevenage, Strood, and Chatham. 



Zone of Mlcnister cor-aiKjiiinitm of Micheldever, Witherington, Quidhampton, 

 Foot's Cray, Southerham (Lewes), Northfleet, New Brompton, Gravesend. and 

 Litcham, Norfolk. 



Zone of Marsupites tesiudUutrins of Ovingdean (Susse.K). TJintdcrimix l)and of 

 Taplow and the Thanet coast. 



Zone of ActinocamK.v (jiuidrdfrni of East Harnham. 



Zone of Bdi'iiniHeUii viiirnninfn of Ballard Head, Farehnm, Clarendon and 

 Norwich. 



Zone of Chlrrri hum fa of Trimingham. 



OsTiiKA s.\RrMKNsi8, sp. ufli: Plate LVIII, figs. G — i». 



Descnption. — Shell thick, higher than long; slightly, modei'ately, or consider- 

 able inequilateral. 



Left valve very conve.x, with the attached surface of variable size. Area large, 

 high, curved slightly or considerably backwai'ds. Free part of valve with small 

 radial folds, and growth-lamella>. Tuner margin Avith a row of small pits. Right 

 valve slightly convex, -with a large area ; surface (except of the earlier part) orna- 

 mented with numerous small radial ribs sepai-ated by linear furrows, and crossed 

 by growth-lamellae. 



4/?i)u/;i«.s.— The high area and the radial folds of the left valve suggest that 

 this species may be related to 0. i<emipln)i<i ; it also resembles some forms of 

 0. BoHcheroni. Moi"e specimens are needed in order to det(>rmine satisfactorily the 

 affinities of this form. 



Tijpe. — \ix Dr. Blackmore's collection. 



Distribution. — Zone of Actiiior.ama.r (jna-'h-ntnsoi Kast llarnliaui, near Salisbury. 



