300 DE. a. S. BEADY ON ENTOMOSTEACA 



more than twice as long as broad. Surface smooth, opaque ; 

 yellowish brown, with transparent patches. Length J^ of an 

 inch ("SS millim.). 



G-enus Chlamtdotheca, De Saussure. 

 (Chlamydotheca, Be Saussure ; ? Cypridea *, Bosquet.) 

 Chlamtdotheca suBGLOBOSA {Sowerby , fide Baird). (Plate 

 XXXVIII. figs. 24-27 a.) 



Cypris subglobosa, Baird, Proc. Zool. Soc. 1859, pi. 63. fig. 2. 



Shell subglobular, tumid : seen from the side, subovate, highest 

 in the middle, height equal to quite half the length, anterior ex- 

 tremity obliquely rounded, posterior narrowed and somewhat 

 produced, rounded off; dorsal margin evenly arched, sloping 

 more steeply behind than in front, slightly sinuated toward either 

 extremity ; ventral margin almost straight : seen from above the 

 outline forms almost a circle, with the anterior and posterior ends 

 produced to acute angles, the anterior much the more attenuated 

 of the two ; width equal to three fourths of the length. The two 

 valves are nearly equal, but the right is much more irregular and 

 more angulated than the left ; its anterior portion forms a sort 

 of outgrowth, which is separated from the rest of the valve by a 

 strongly marked sulcus ; the ventral margin is deeply and abruptly 

 sinuated near the middle, the posterior extremity forming a pro- 

 duced and somewhat angulated beak and bearing a series of more 

 or less distinct serratures ; similar teeth are found also at both 



* The following definition of the genus Ci/pridea is given by Professor T. 

 Rupert Jones, F.R.S., in a paper, " On the Ostracoda of the Purbeck Forma- 

 tion" (Quarterly Journal of the Geological Society, August 1885, p. 336) : — 



" Carapace-valves subtriaugular, obovate, or ovate-oblong ; convex in the 

 middle ; broad (high) at the anterior third, narrower behind ; one or both ends 

 obliquely rounded ; somewhat compressed anteriorly ; notched at the antero- 

 ventral angle, behind a small beak-like process ; sometimes having only a slight 

 indentation below, and behind a thickening of the antero-ventral angle ; some- 

 times this is traceable only by a curvature of the edge inside. Edge-view more 

 or less narrow-ovate ; end-view subovate. Surface punctate, sometimes almost 

 smooth, often tuberculate ; tubercles small or large, variously disposed. The 

 hinge-margin is definitely straight along the middle third or more of the dorsal 

 edge, with the hinge-angles more or less defined, and is oblique to the main 

 axis of the valve. The left valve is the largest, and receives the dorsal edge and 

 a straight ridge of the other valve in grooves on its dorsal and ventral contact- 

 margins, the outer edge of the ventral margin of the left valve overlapping that 

 of the right valve. The ridges and furrows or ledges of contact vary in inten- 

 sity in different individuals." 



