«4 



MESOZOIC AND CAINOZOIC DINOFLAGELLATE CYSTS 



Description. C. inodes has a fibrous body wall, bearing processes which give the 

 reflected tabulation typical of this genus. The variability in the number of processes, 

 noticed by Klumpp, has also been observed in the London Clay forms, especially in 

 the sulcal region. The processes are either hollow, open distally with an ellipsoidal 

 cross-section or taeniate. The process walls of the London Clay specimens are 

 extremely fibrous and appear to be thinner than in the type material, perhaps due to 

 oxidation within the sediment. 



C. inodes has been recorded from sediments ranging from the Lower Eocene to 

 Middle Miocene in age. 



Material (Figured). B.M.(N.H.) slide ¥.51745(1). 2 feet above base of London 

 Clay ; Whitecliff, Isle of Wight. 



Dimensions. V. 5 1745 : diameter of central body 46 by 48^, length of processes 

 19-24PL. Range in type material (Klumpp 1953) : diameter of central body 52-76^, 

 length of processes 20-40jx. Range of London Clay forms : diameter of central 

 body 46-7610., length of processes i4-33fx. Number of specimens measured, 5. 



Cordosphaeridium gracilis (Eisenack) 

 PI. 3, fig. 8 ; PL 11, figs. 4, 6, 7 ; Text-fig. 19 



1938. Hystrichosphaera cf. ramosa (Ehr.) ; Eisenack : 186, text-fig. 1. 



1954. Hystrichosphaeridium inodes subsp. gracilis Eisenack : 66, pi. 3, fig. 17 ; pi. 10, figs. 



3-8 ; 112, figs. 7, 21. 

 1961. Hystrichosphaeridium inodes subsp. gracilis Eisenack ; Gerlach: 187, pi. 28, fig. 6. 

 1963&. Cordosphaeridium inodes subsp. gracilis (Eisenack) Eisenack, pi. 29, fig. 2. 



Fig. 18. Cordosphaeridium inodes (Klumpp). A specimen from the London Clay, 

 apical view ; right, antapical view, by transparency. x c. 650. 



Left, 



