60 



J. WATSON, S.J. LYDON & N.A. HARRISON 



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B 



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Fig. 24 A-I Pseudotorellia vunesiana sp. nov. A, apical portion of leaf with tip missing, LM, V.64554, x 25; B, holotype; leaf fragment opened up to show 

 stomata confined to one surface (?lower), V.64555, x 25; C-L, all from V.64556; C, lower cuticle with stomata. LM. x 125; D, inside surface of lower 

 cuticle showing stomata arranged in three indistinct bands, SEM, x 75; E, four stomata viewed from the inside. SEM, x 250; F, single stoma viewed from 

 the inside surrounded by rings of subsidiary and encircling cells, SEM, x 250; G, H, stomata showing oval rim to pit (in top plane of focus) and polar 

 appendages to guard cells (in lower plane of focus), LM, x 500; I, stoma viewed from the inside with distinct cutinization of ventral as well as dorsal 

 periclinal walls of guard cells, SEM, x 500; J, crater-like stomatal pit, SEM, x 500; K, cut section through a stomatal pit, SEM, x 500; L, inside surface 

 of upper cuticle showing outlines of rectangular cells and longitudinal bars, SEM, x 250. 



of a scar at the base of the leaf and the occurrence of P. linkii needle 

 leaves in concentrated deposits (brachyblasts of Vakhrameev 1971) 

 in the Wealden of northwest Germany are thought to indicate sea- 



sonal leaf abscission. Sulcatocladus robustus shoots (Watson & 

 Harrison 1998), first attributed to this species by Dunker (1846: 18), 

 and later by Wilde ( 1991 ) but not separately named, are regarded as 



