124 



POST-TERTIARY ENTOMOSTRACA. 



rounded, superior margin excessively and evenly arched, inferior rather deeply sinuated' 

 in the middle ; seen from above compressed, ovate, pointed in front, rounded off behind, 

 greatest vi^idth situated near the middle and equal to a little more than one third of the 

 length. Surface of the shell smooth and polished (recent specimens all usually more or 

 less marked vs^ith distant but rather large circular impressions) ; colour yellov^ish-brow^n, 

 sometimes with pellucid colourless patches. 

 Length, ^th of an inch. 



Distribution. Becent. — Great Britain, Switzerland, Germany, Bohemia, Tyrol. 



Fossil. — Hornsea and Branston Fen, England ; Dipple, Scotland. 



2. Cypris salina. Brad?/. Plate I, figs. 17 — 19. 



1850. Cypbis strigata, Baird. Brit. Entom., p. 157. 



1868. — SALINA, Brady. Monog. Recent Brit. Ostr., p. 368, pi, xxvi, figs, 



8—13. 



Shell, as seen from the side, broadly reniform, greatest height situated in the middle and 

 equal to nearly two thirds of the length, extremities equally and broadly rounded, superior 

 margin boldly and evenly arched, inferior rather deeply incurved ; outline, as seen from 

 above, narrowly ovate, anterior extremity much attenuated and bluntly mucronate, 

 posterior subacuminate, greatest width considerably less than half the length, situated in 

 the middle. Hinge- and contact-margins of the valves very flexuous, the latter thickened 

 and prominent. Surface of the shell smooth or very slightly pubescent. Recent 

 specimens beautifully marked with brown striae and blotches. 

 Length, -^th of an inch. 



Distribution. Becent. — Great Britain. • 



Fossil. — Crofthead, Scotland. 



It may perhaps be doubtful whether the specimen here described is properly 

 referable to C. salina, as it differs from the recent specimens of that species not only in 

 being considerably smaller but also to some extent in lateral outline which is more 

 nearly reniform. The smaller size may depend upon immaturity, and the differences of 

 shape are not sufficient to warrant its separation as a distinct species ; the absence of 

 colouring cannot be considered important in a fossil example, and, indeed, sometimes 

 occurs in recent specimens. 



3. Cypris virens {Jurine). Plate II, figs. 27, 28. 



1820. MoNOCULUs VIRENS, Jurine. Hist, des Monocles, p. 1 74, pi. xviii, figs. 15, 16, 

 1850, Cypris tristriata, Baird. Brit. Entom., p. 152, t. xviii, figs. 1, 1 a—i, 2, 3. 



