REVISION OF THE ENGLISH WEALDEN FLORA 





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Fig. 15 A-F Ginkgoites nannyoggiae sp. nov. A, E from Wessex Formation, Worbarrow Bay. Dorset. B, D from Wessex Formation. Mupe Bay. Dorset. C, 

 F show tfie holotype, from Fairlight Clays facies of Ashdown Beds. Galley Hill. Sussex: all lower cuticle. A, random arrangement of papillate ordinary 

 epidermal cells, V.64547, LM, x 125; B, outer surface of cuticle showing stomatal distribution and papillate surface. V.64546. SEM. x 125: C, inner 

 surface of cuticle showing randomly arranged polygonal, isodiametric ordinary epidermal cells and scattered stomata, V.64545. SEM. x 125: D, outside 

 of single stoma showing small, flattened papillae overhanging pit, V.64546, SEM, x 750: E, 2 stomata with large protruding papillae, V.64547, LM, x 

 500; F, single stoma viewed from inside showing narrow dorsal plates of guard cells which bear fme radiating striae, V.64545, SEM, x 750. 



is smooth and featureless (Fig. 19B). Fig. 19C shows the stomata 

 scattered and randomly orientated. The guard cells, with well 

 cutinized 'axe-head-shaped' dorsal plates and inner anticlinal walls 

 (Fig. 19F), are sunken beneath a ring of typically 5 subsidiary cells, 

 and are sometimes partially exposed (Fig. 1 9D). The subsidiary cells 



sometimes bear flat papillae which overhang the round or square 

 stomatal pit (Fig. 19E); others have a simple rim (Fig. 19D). This is 

 a character that varies a great deal between specimens but is fairly 

 constant for any particular specimen. Clearly further finds, particu- 

 larly less fragmentary portions of leaf, are needed to enhance our 



