182 Mr. Gr. S. Brady on Marine Ostracoda 



CytJiere convoluta, nov. sp. (Plate XII. figs. 3, 4.) 



Carapace of the female (?), seen from the side, subqnadrangular, 

 highest in front of the middle ; greatest height equal to 

 about two-thirds of the length : anterior extremity broadly 

 rounded ; posterior produced below the middle into a broad 

 slightly dentate process, emarginate above : superior margin 

 slightly arched in front, excavated behind the middle ; in- 

 ferior almost straight, bending upwards behind. Seen from 

 above, the outline is irregularly ovate or subhexagonal, 

 constricted in the middle, broadly mucronate before and 

 behind ; greatest width near the middle, equal to more than 

 half the length. Surface of the valves sculptured with pro- 

 minent, flexuous, reticulating ridges, and with a prominent 

 sharp crest running entirely round and a little within the 

 margins, but less conspicuous posteriorly. Length ^^ inch. 



Cytheridea punctillataj Brady. 



Cytheridea punctillata, Brady, Ann. & Mag. Nat. Hist. 1865, vol. xvi. p. 189, 

 pi. 9. figs. 9-11. 



Carapace of the female (?), seen from the side, subreniform, 

 highest in front of the middle ; greatest height equal to half 

 the length : anterior extremity well and evenly, posterior 

 obtusely rounded : superior margin gently arched, inferior 

 nearly straight. Seen from above, ovate, pointed in front, 

 broadly rounded behind, scarcely constricted in the middle ; 

 greatest width near the posterior extremity, equal to about 

 half the length. Surface marked with closely set rounded 

 puncta, and a few minute round papillae. 



I cannot distinguish the examples here described from the 

 European species Cytheridea punctillata^ which occurs abun- 

 dantly in some parts of the British and Scandinavian seas, 

 and also, as a fossil, in the posttertiary clays. There are, 

 indeed, some slight differences of form and sculpturing ; but 

 these seem subject to much variation, and are certainly not of 

 sufficient importance to warrant our regarding them as indices 

 of specific rank. 



Cytheridea spinulosay nov. sp. (Plate XIII. figs. 1-6.) 



Structure of the shell very robust and thick ; valves tumid. 

 As seen from the side, almost elliptical, highest near the 

 middle ; greatest height equal to more than half the length ; 

 extremities broadly and obtusely rounded, and bearing be- 

 low the middle a series of (about twelve on the anterior and 

 six on the posterior) short roimded marginal teeth : superior 

 margin feebly arched, highest in the middle ; inferior almost 



