from Southern Niycrui, T.'7 



inequilatcriil ; co-tic fiiio, muncrous (about 30), separated hy 

 narrow grooves, convex, sinootli. 



Dimensions (largest example). — Length =-0, height = 

 20 nun. 



h'ciiiiirks. — There are several examples of this form of 

 Cttri/ium, which appears to be one of the prevailing shells of 

 tiiese deposits. The C')sti« are considerably worn, especially 

 near the ventral mar<j[in, but they are quite as numerous and 

 fine as in young e\i\m\)\es o( decorticatiim from the Etiglisji 

 Crag contained in the tSearles Wood Collection at the Biitish 

 Mu--eum. Like them, also, the costse become eroded and avo 

 frequently divitled by a (iue centr;il groove. Tbe s[ ecimens 

 may represent the young forms of this species, in which the 

 ribs are continuous over the surface of the valve, whereas 

 adult exam[)les recorded from England are without cosfa3 on 

 the posterior side. 



Tiiey may be said also to show some resemblance to young 

 exam|)les of Cardium miirico/um, an Atlantic species (West 

 Indies) of Linna?us (Syst. Natura?, 1 To.S, ed. x. p. 679), as 

 determined in the Zoological Depaitment of the British 

 Museum, especially in the number and general formation of 

 the costa?. 



(?) Gastratta sp. (PI. VL fiii?. 8, 9) and associated 

 Fish-scale (Pi. VI. Hg. Ki). 



Description. — Tiie collection contains a fragmentary right 

 valve of what is doubtfully referred to the genus Gastranc, 

 It is of oval-oblong shape and covered with prouiinent, equi- 

 distant, concentric laminations of slightly infundibidiforni 

 character, separated by well im[)ressed sulcations; no radial 

 ornamentation is visible. 



The umbonal region is moderately elevated, oblique, and 

 anterior; the margins of the front and ventral areas are 

 rounded, the postero-dorsal border is straight and oblique, 

 whilst the posterior surface is more or less truncated. 



Dimensions. — Height = 18, length = 22 mm. 



lieniarks. — It is in the regular character of the costw, the 

 truncated posterior side, and the elevated umbonal region, 

 which suggests at first glance a relationship to Gastrana, 

 although the concentric sculpture of that genus shows no in- 

 fundibuliform character as in the present specimen. Without 

 more complete material it is difficult to place such a fragment 

 in its true generic position, and so for present pur[)oses it 

 has been compared with examples of Gastrava laminosa, 

 J. de C. Sowerby, from the British Pliocene beds, a form 

 closely allied to the lecent frag His of Linnaeus. 



