126 POST-TERTIARY ENTOMOSTRACA. 



5. CiTRis LiEvis, Mailer. Plate I, figs. 25 — 28. 



1785. Cypris ljsvis, Muller. Eatomostraca, p. 52, tab. iii, figs. 7 — 9. 

 1851. — ? PANTHERINA, Fischer. Ueber das genus Cypris, p. 163, tab. xi, figs. 



6—8. 



1853. — OVUM, Lilljeborg. De Crustaceis, p. 113, tab. x, figs. 13 — 15. 



1854. — (Cypria) — , Zenker. Auat.-syst. Studien, p. 70, tab. 3 b. 

 1856. — OVUM, Jones. Monog. Tert. Entom., p. 14, pi. i, figs. 4 a, 4 b. 



1868. Cypris l^vis, Brady. Monog. Recent Brit. Ostrac, p. 374, pi. xxiv, figs. 



21 — 26 ; and pi. xxxvi, fig. 5. 



Shell very tumid ; seen from tlie side forming almost three fourths of a circle, 

 extremities broadly rounded, superior margin excessively arched, regularly curved behind, 

 but somevi'hat flattened in front of the middle ; inferior convex towards the extremities, 

 straight in the middle ; seen from above, ovate, vi'idest in the middle, greatest width 

 nearly equalling the height, anterior extremity acuminate, posterior broadly rounded. 

 Surface of the shell perfectly smooth and polished ; colour chestnut brown. 

 Length, -^th of an inch. 



We were at one time disposed to regard this as a new and distinct form ; but, after 

 examining specimens of C. lavis from many widely separated localities, it seems to be so 

 variable in respect of size, outline, and colouring, that we can scarcely avoid the conclu- 

 sion that our Whittlesea specimens belong to the same category. The form figured in 

 the ' Monograph of Recent British Ostracoda,' though apparently common in the county 

 of Durham in a living state, is, perhaps, more pronounced as to the tumidity of the 

 posterior and tapering of the anterior extremity than is usual with the species. 



Distribution. Recent. — Great Britain, Denmark, Germany. 



Fossil. — Cambridgeshire, Whittlesea, England; Dipple, Scotland. 



6. Cypris cinerea, Brady. Plate II, figs. 6, 7. 



1868. Cypris cinerea, Brady. Monog. Recent Brit. Ostrac, p. 374, pi. xxiv, figs. 



39 — 42, and pi. xxxvi, fig. 7. 



Carapace oval, tumid, higher in front than behind ; greatest height equal to nearly 

 two thirds of the length. Anterior margin broad and well rounded, posterior narrowed 

 and rather obliquely rounded. Ventral margin straight or very slightly incurved, dorsal 

 forming a flattened arch, and sloping more steeply behind than in front. Seen from 

 above, rhomboidal or lozenge-shaped, greatest width in the middle, and equal to more 

 than half the length ; from the middle the sides taper evenly towards the extremities, the 



