MESOZOIC AND CAINOZOIC DINOFLAGELLATE CYSTS 95 



Remarks. The size, number and nature of the processes make it easy to distin- 

 guish P. laminaspinosum from all previously described species. The processes are 

 longer and more distinctly tubular than is usual for this genus. If more species of 

 this form are discovered a new genus should be erected to differentiate these types 

 from the typical species of Polysphaeridium. 



OTHER SPECIES 



The following species are here tentatively referred to the genus Polysphaeridium 

 on the basis of the form of the processes although an apical archaeopyle has not been 

 recorded in any of them. 



? Polysphaeridium asperum (Maier 1959). Miocene ; Germany. 



1 Polysphaeridium deflandrei (Valensi 1947). Middle Jurassic ; France. 



? Polysphaeridium cf. elegantulum (Wiler 1956). Tertiary ; Germany. 



? Polysphaeridium fabium (Tasch, McClure & Oftedahl 1964). Lower Cretaceous ; 

 U.S.A. 



} Polysphaeridium fluctuans (Pastiels 1948). Eocene ; France. 



? Polysphaeridium follium (Tasch, McClure & Oftedahl 1964). Lower Cretaceous ; 

 U.S.A. 



1 Polysphaeridium fucosum (Valensi 1955). Cretaceous ; France. 



^Polysphaeridium marsupium (Tasch, McClure & Oftedahl 1964). Lower 

 Cretaceous ; U.S.A. 



? Polysphaeridium major (Lejeune-Carpentier 1940). Upper Cretaceous ; Bel- 

 gium. 



? Polysphaeridium patdinae (Valensi 1953). Middle Jurassic ; France. 



? Polysphaeridium perovatum (Tasch, McClure & Oftedahl 1964). Lower Creta- 

 ceous ; U.S.A. 



IPolysphaeridium polypes {=H. recurvatum subsp. polypes Cookson & Eisenack 

 1962). Lower-?Upper Cretaceous ; Australia. 



^Polysphaeridium rhabdophorum (Valensi 1955). Cretaceous ; France. 



IPolysphaeridium simplex (White 1842). Upper Cretaceous ; England. 



^Polysphaeridium tribrachiosum (Tasch, McClure & Oftedahl 1964). Lower 

 Cretaceous ; U.S.A. 



IPolysphaeridium zoharyi (Rossignol 1962). Pleistocene ; Israel. 



Genus DIPHYES Cookson 1965 : 85 



Emended diagnosis. Chorate cysts with ovoidal to spherical central body 

 composed of two layers. Processes numerous, 1 to 4 per plate area, hollow and 

 either open or closed distally. Large antapical process occurring opposite apical 

 archaeopyle. 



Type species. Hystrichosphaeridium colligerum Deflandre & Cookson 1955. 

 Eocene ; Australia. 



