20 TERTIARY ENTOMOSTRACA OF ENGLAND. 



p. 257, pi. ix), with Nummulites elegans, Sow. (N. Wemmelensis, var. Prestwichiana) ; 

 it is abundant in the Barton Clay at Barton and Highcliff. It occurs also at 

 Colwell Bay and Bracklesham. (British Museum.) 



4. Cythere Wetherelli, Jones. 



Cythere Wetheeelli, Jones. Quart. Journ. Geol. Soc, vol. x, 1854, p. 161, pi. iii, 



fig. 9 ; Monogr. Tert. Entom., 1857, p. 27, pi. iv, 

 fig. 6 ; Brady, Trans. Zool. Soc, vol. x, 1878, 

 p. 890, pi. Ixiv, figs. 7 a—d. 



Loxoconcha — Geol. Mag., 1870, pp. 156 and 158. 



This has somewhat of the shape and profile of a Loxoconcha. Its hinge is 

 almost the same as that referred to Gyprideis in the ' Monogr. Tert. Entom.,' p. 21, 

 but modifications of such a hingement are found also in both Cythere and 

 Gytheridea ; it cannot, therefore, be taken as a differential character. 



This neat and delicate species is not uncommon in the Tertiary Sands 

 (Headon Series) of Colwell Bay, and in an oyster-band of this formation at the 

 same locality. It has been found also at Barton. (British Museum.) It is rare 

 in the Antwerp Crag. 



5. Cythere consobrina, Jones. Plate III, figs. 4 a, b. 



Cythere consobrina, Jones. Monogr. Tert. Entom., 1857, p. 27. 



This form, from the Barton Clay, described but not figured in the Monograph 

 of 1857, is now figured from the original specimen preserved in the British 

 Museum. We may remark that its supposed alliance to G. attenuata (Ibid., p. 28) 

 does not hold good ; the latter is a Pseudocythere. 



6. Cythere venttstula, Jones 8f Sherborn. Plate I, figs. 23 a, b. 



Cythere venustula, Jones & Sherborn. Geol. Mag., 1887, p. 388. 



Oblong, rounded at the ends, broadly oblique in front, semicircular behind ; 

 straight on the ventral, oblique dorsally by the swelling of the anterior hinge- 

 joint. Depressed on the front half, but more convex behind. Surface orna- 

 mented with a neat open network of delicate meshes, lying obliquely from the 

 postero-dorsal to the antero-ventral region. 



From the Belosepia-bed at Bracklesham. (British Museum.) 



