MESOZOIC AND CAINOZOIC DINOFLAGELLATE CYSTS 



177 



Processes of two types, large ones with quadrate bases, cylindrical or tapering with 

 open ends, and small slender processes, with ends open or closed. Antapical 

 process much longer than others. Tabulation typical for genus. Number of slender 

 processes on each cingular plate limited to two. Cingulum helicoidal. Anterior 

 sulcal process considerably larger than other sulcals. 



Holotype. B.M.(N.H.) slide ¥.51958(1), London Clay ; Sheppey, Kent, 

 sample Sh. 3. 



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Fig. 46. Hystrichokolpoma eisenacki sp. nov. Ventral view of holotype showing 

 the Tabulation. The archaeopyle is shaded. 



