30 TERTIARY ENTOMOSTRACA OF ENGLAND. 



33 and 33*. Cythere costellata (Roemer), var. triangulata, Jones 8f Sherborn, 



Plate I, fig. 21. 



Cythere costellata (Roemer), var. teiangulata, Jones Sf Sherborn. Geol. Mag., 



1887, p. 450. 



The specimen under notice is relatively shorter, broader (higher), more 

 triangular, and with sharper ridges than the figure in the ' Monograph,' 1857, 

 p. 32, pi. vii, fig. 21. The anterior hinge is more prominent, and the front margin 

 rather oblique. It is also narrower behind, ending with three small spines or 

 denticles. The edge view is acute ovate. 



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

 Cythere costellata was figured and described in the ' Monograph Post-Tert. 

 Entom.,' 1874, p. 152, pi. xvi, figs. 13 — 15, from Selsey, and there recognised as 

 being probably of Tertiary date, though found in the superficial mud. 



34. Cythere gyriplioata, Jones 8f Sherborn. Plate I, figs. 17 a, b. 



Cythebe gybiplicata, Jones Sf Sherborn. Geol. Mag., 1887, p. 391. 



Narrow-suboval in outline, hinge-line slightly convex, and distinct. Ends 

 rounded, narrow behind, somewhat oblique in front. Surface sculptured with 

 delicate longitudinal ridges, arranged concentrically towards the margins, and 

 united by smaller transverse ridges. 



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

 The nearest species we know of is Bosquet's G. multicostata, ' Entom. Tert.,' 

 p. 59, pi. ii, fig. 12; but this is very much coarser and broader, and without any 

 sign of reticulation. 



35 and 35*. Cythere sorobiculo-plicata, et var. recta, Jones. 



Citiieee scbobiculo-plicata, et var. eecta, Jones. Monogr. Tert. Entom., 1857, 



p. 33, pi. vi, figs. 4, 6, 9 ; 

 Geol. Mag., 1887, p. 452. 



A figure of this species was reproduced in the 'Geol. Mag.,' 1887, p. 452, 

 pi. xi, fig. 8, from the 'Monograph Tert. Entom.,' 1857, as one of the forms 

 belonging to the London Clay of Finchley and Copenhagen Fields ; the species 



