42 



MESOZOIC AND CAINOZOIC DINOFLAGELL ATE CYSTS 



Hystrichosphaera buccina sp. nov. 

 PI. 4, fig. i ; Text-figs. 10, n 

 Derivation of name. Latin, buccina, trumpet — with reference to the shape of 

 the processes. 



Diagnosis. A species of Hystrichosphaera with central body composed of thick 

 endophragm and thinner periphragm, the latter giving rise to gonal processes and 



Fig. io. Hystrichosphaera buccina sp. nov. Holotype, ventral view. x c.iooo. 



'# 



Fig. ii. Hystrichosphaera buccina sp. nov. A specimen from the London Clay, 



ventral view. x c.iooo. 



