PLATE 4 

 Clypeina 



Fig. i. Clypeina marteli Emberger, transverse thin-section, X28. Cretaceous, Valanginian ; 

 Hugf, Southern Oman, Arabia. V. 52042. 



Fig. 2. Clypeina merienda Elliott, oblique-transverse thin-section through verticil to show 

 bases of tubules and part of central ring. X35. Palaeocene, Sinjar Formation ; Koi Sanjak, 

 Erbil Liwa, Iraq. V. 52043. 



Figs. 3, 7, 8. C. merienda, thin sections, X28. Palaeocene, Sinjar Limestone. 3. Trans- 

 verse cut of broken verticil. Sirwan, Sulemania Liwa, Iraq. V. 41586. 7. Oblique cut of 

 successive verticils. Koi Sanjak, Erbil Liwa, Iraq. V. 52043. 8. Vertical-tangential cut of 

 numerous successive verticils of one plant. Sirwan, Sulemania Liwa, Iraq. V. 41587. 



Figs. 4, 5, 6. C. jurassica, solid (dissociated) verticils, showing top, side and bottom appear- 

 ances, X28. Upper Jurassic, Arab zone ; subsurface, Dukhan No. 2 Well, Qatar, Arabia. 

 V. 52044, V. 52045, V. 52046. 



