334 Mr. F. Chapman on Ostracoda 



towards the lowest third ; the dorsal margin well arched ; 

 the extremities of the valves rather obliquely rounded, with 

 the anterior broader than the posterior. Surface of valves 

 well and evenly rounded. Edge- view long and acutely oval; 

 end-view broadl}^ oval. Length 1*3 millim. ; height -48 

 miliim. ; thickness '38 millim. 



Fis:. 1. 



Macrocypris simplex, sp. u. a, left side ; b, ventral aspect ; 

 c, end aspect. X 20. 



This form comes nearest to Macrocypris concinna^ J. & H.*, 

 amongst Cretaceous species, but differs in being proportion- 

 ately longer ; its ventral margin is more distinctly incurved 

 and the anterior extremity, as seen from tlie side, is more 

 acute than in M. concinna, Macrocypris setigera of G. S. 

 Brady f is, perhaps, the nearest in outline to the above species, 

 but the ventral side of the recent form is nearly straight and 

 the dorsal more strongly arched ; the anterior end is also 

 less acute in edge-view. 



One carapace from the Greensand of Swaffhara. 



Macrocypris Muensteriana, Jones and Hinde. 



Macrocypris Muensteriana, Jones and Hinde, 1890, Siippl. Mon. Cret. 

 Entom. pp. 10, 11, pi. ii. figs. 42 and 45—47. 



This species is already known from the Wliite Chalk and 

 the " Chalk detritus " of Kent, and also from the Gault of 

 Meux's Well, London. 



One carapace, measuring only "475 millim. in length and 

 probably a young form, was obtained from the Cambridge 

 Greensand of Swaffham. 



* Suppl. Mon. Cret. Eutom. p. 11, pi. ii. figs. G6, G7. 



■j- < Challenger' Reports, 1880, Zoology, part iii. p. 4-3, pi. i. figs. 1 a-d. 



