'688 MR. F. CHAPMAN ON THE BARGATE BEDS OF SURREY. [Nov. 1 894, 

 VI. OsTRACODA AND PoRAMINTFERA OE THE LOWER GREENSAND. 



The Lower Greensand strata of the 8.E. of England are remark- 

 ably poor in the actual tests of foraminifera and other minute 

 fossils, the former being hitherto represented only by internal casts in 

 glauconite. Nevertheless, since glauconite-grains play so important 

 a part in the formation of these Greensand beds, foraminifera must 

 have existed in prodigious abundance at the time when these 

 deposits were laid down. 



The Speeton Clay of Yorkshire, also the Hilsthon and other 

 Neocomian beds in North Germany and elsewhere, have already 

 yielded an abundant foraminiferal fauna. 



It is interesting, therefore, to find the calcareous tests of fora- 

 minifera and the carapaces of ostracoda* in the Bargate Beds of 

 Surrey. Whether this entire fauna was contemporaneous with the 

 beds in which it occurs has yet to be proved ; nevertheless, it is 

 noteworthy that among the species and varieties of foraminifera 

 found there are undoubted Lower Greensand forms. 



VII. Ostracoda from the Bargate Pebble-beds of Littleton 

 and of St. Martha's Hill (Chilworth). 



[These all belong to the Cytheridce.~] 



1. Ctthere vesiculosa, sp. nov. (PI. XXXIII. fig. 1 a, b, c.) 



Valve quadrate, but rounded in front and bluntly pointed 

 posteriorly : the surface sloping away from the ventral margin to 

 the front and dorsal edges. Ventral face flat with the edges of the 

 valves forming a flanged border, which passes along the posterior 

 end of the valve. Dorsal edge short, locally swollen beyond the 

 anterior hinge and curving into the posterior edge behind. The 

 surface of the valve is irregularly swollen with rounded lumpy 

 prominences. There are four of these protuberances situated 

 towards the dorsal and central area, and a large and more pro- 

 minent one projecting from near the middle of the ventral edge of 

 the carapace ; the presence of this last process shows the species 

 to have a slight affinity towards the genus Cyiheropteron. Length 



iV in - C 4 ? mm 0- 



This species somewhat resembles 0. Cluthce, Brady, Crosskey, & 



Robertson, 1 and C. globulifera, Brady a ; but it differs from them 



chiefly in the arrangement of the knobs. 



Occurrence : one valve in clay of Bargate Pebble-beds, Littleton. 



2. Cythereis ornatissima (Beuss). 



Cytherina ornatissima, Reuss, ' Verstein. bohm. Kreideform./ 

 . pt. ii. (1846) p. 104, pi. xxiv. figs. 12 & 18. 



Cythereis ornatissima, Jones & Hinde, Mon. Cret. Entom. 

 Suppl., Pal. Soc. (1890) p. 21, pi. ii. figs. 1-7, 15, 16; pi. iv. 



.figs. 7, 8. 



1 Mon. Post-Tert. Entom., Pal. Soc. (1874) p. 153, pi. xiii. figs. 16, 17. 



2 Ibid. p. .155, pi. ix. figs. 18-20 ; pi. xii. figs. 11, 12; pi. xv. figs. 19, 20. 



