REVISION OF THE ENGLISH WEALDEN FLORA 



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Fig. lOA-F Ginkgoites weatherwaxiae sp. nov. All cuticle of upper surface of leaf. A, stomatal distribution and arrangement of ordinary epidermal cells in 

 rows, V.64541, LM, x 125; B, inner surface of cuticle showing stomatal distribution and arrangement of ordinary epidermal cells in rows. V.64542. SEM, x 

 125; C, outer surface of cuticle showing ridging on left, V.64542, SEM, x 125; D, outer surface of cuticle with slit-like stomatal pit, V.64542, SEM. x 750; 

 E, single stoma showing ring of subsidiary cells with one papilla overhanging the stomatal pit, V.6454 1 , LM. x 750; F, single stoma viewed from inside 

 showing guard cells with thickly cutinized semi-circular dorsal plates and inner anticlinal walls around the stomatal slit, V.64542, SEM, x 750. 



the work of various leaf litter feeders. However, damage by aphids is 

 well known to introduce infestations of fungi and bacteria, with 

 subsequent decay and enlargement of the puncture. Damage com- 

 prising small circular perforations and even semicircular 'nibbles' 

 can only be caused by mandibulate insects such as beetles 

 (Coleoptera) and not haustellate ones such as bugs. Recent leaf 



beetles and weevils commonly produce holes in leaves of seed 

 plants. Beetles are the most common insect order in the Wealden and 

 include plant feeders (Jarzembowski 1995). Fossil damage such as 

 that on the leaves of G. weatherwaxiae can be referred to the 

 ichnogenus Phagophytichnus. 



The stomatal apparatus of both surfaces is typically oval in outline 



