66 



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Fig. 28 A-F Sciadopity aides greeboana sp. nov. All upper cuticles of dispersed leaves from the Fairlight Clay at Galley Hill. Sussex. A, cuticle showing 

 narrow cells over the midline and one stray stoma. LM. V.64587. x 1 25; B, typical appearance of the outside surface with longitudinal ridges over files of 

 epidermal cells, SEM, V.64588, x 1 25; C, less common appearance of the outside surface, with hollow papillae, SEM, V.64588. x 500; D, vertical section 

 through upper cuticle (inside uppermost) showing thick outer and thin inner periclinal walls to epidermal cells, SEM, V.64588, x 2500; E, inside view 

 showing hypodermal cutinization draped beneath epidermal cell outlines, SEM, V.64588, x 500; F, outlines of epidermal cells and larger hypodermal 

 cells. LM, V.64587, x 300. 



They differ from those of the stomatal-free regions in having domed 

 outer surfaces and longitudinal ridges which are broad and often 

 restricted to one cell (Fig. 29A-C, G). The ridges are frequently 

 broken up into a row of small circular thickenings like a string of 

 beads (Fig. 29A, C). The stomata themselves are also longitudinally 

 aligned, although not forming distinct files (Figs 270; 29A, B). The 

 stomatal pits are spindle-shaped (Fig. 29E, G) and flanked by one or 



two elongate subsidiary cells on each side (Fig. 29F, H). The lateral 

 subsidiary cells have domed surface walls (Fig. 29G, H) but usually 

 lack any extra surface thickening. The polar subsidiary cells, one at 

 each end of the pit, have a longitudinal ridge over the outside and are 

 quite indistinct from the ordinary epidermal cells (Fig. 29D, F). The 

 guard cells are sunken beneath the level of the subsidiary cells (Fig. 

 29D, F, H). They have strongly cutinized dorsal plates and at both 



Fig. 29 A-H Sciadopityoides greeboana sp. nov. All lower cuticles of dispersed leaves from the Fairlight Clay at Galley Hill, East Sussex. A, B, E, F, 

 V.64587; C, D, G, H, V.64588. A, stomatal band with single bead-like papillae on the files of ordinary epidermal cells, LM, x 125. B, stomata with spindle- 

 shaped pits and longitudinal ridges of thickening over ordinary epidermal cells, LM, x 250: C, outside surface of stomatal band with ridges and rows of 

 papillae over the ordinary epidermal cells, SEM, x 250; D, inside surface of stomatal band showing longitudinal files of ordinary epidermal cells and 

 longitudinally aligned stomata, SEM, x 250; E, stoma with outside surface of cuticle in focus. Stomatal pit spindle-shaped, longitudinal ridges on ordinary 

 epidermal cells, LM, x 750; F, same stoma as Fig. E, with inside surface of cuticle in focus showing guard cells with strongly cutinized dorsal plates and 

 polar appendages; one distinct subsidiary cell on each side of the guard cells, LM, x 750; G, stoma viewed from the outside with longitudinal ridges and 

 distinct bead-like papillae on surrounding cells, SEM, x 750; H, stoma with ventral as well as dorsal cutinization of the guard cells, SEM, x 750. 



