. Bulletin of the Natural Histort Museum. Geology series. REVISION OF THE ENGLISH WEALDEN FLORA 69. Fig. 31 A-H Sulcalocladus robustus Watson & Harrison. A, B, C, unmacerated shoot fragments showing leaf-scars and decurrent leaf-bases separated by sutures. Ai, ; Aii, Wealden, Duingen, North West Germany, x B, C, two sides of same shoot from English Wealden at Worbarrow Bay, Dorset. , x 5; D, cuticle of decurrent leaf-base with lower margin of leaf scar at top. Galley Hill. East Sussex, x 25; E, cuticle of decurrent leaf-base showing thinner cuticle of l
. Bulletin of the Natural Histort Museum. Geology series. REVISION OF THE ENGLISH WEALDEN FLORA 69. Fig. 31 A-H Sulcalocladus robustus Watson & Harrison. A, B, C, unmacerated shoot fragments showing leaf-scars and decurrent leaf-bases separated by sutures. Ai, ; Aii, Wealden, Duingen, North West Germany, x B, C, two sides of same shoot from English Wealden at Worbarrow Bay, Dorset. , x 5; D, cuticle of decurrent leaf-base with lower margin of leaf scar at top. Galley Hill. East Sussex, x 25; E, cuticle of decurrent leaf-base showing thinner cuticle of longitudinal sutures at each side. Indentation at top is lower part of leaf scar, , holotype. Wealden; Duingen, North West Germany. LM, x 60; F, stoma on leaf-base cuticle surrounded by epidermal cells with pustules, , holotype. Wealden; Duingen, North West Germany, LM, x 125; G, stoma viewed from inside showing cutinization of dorsal and ventral walls of guard cells, Galley Hill, East Sussex, SEM, x 750; H, outside view of stomatal pit, overhung by subsidiary cell papillae. , dispersed cuticle from Wealden; Duingen. North West Germany, SEM, x 750, Yorkshire Jurassic and Mirovia szaferi Reymanowna (1985) from the Jurassic of Poland. Manum (1987) suggested that nibbling by insects might be the explanation in S. macrophylla. Harris (1979: 138) entertained the possibihty that the leaves of B. dura had a hydathode at the tip which would be easily lost during fossilisation. The expansion of the midrib in B. dura iust below the tip appeared to support this but the vascular nature of the midrib has now been questioned (Watson & Harrison 1998) though this needs further investigation. Whatever the outcome for S. dura, there is no evidence to support the presence of terminal hydathodes in S. greeboana (or in P. linkii) and the lack of any insect damage elsewhere would appear to make Manum's suggestion unlikely. In the absence of any evi- dence to the cont
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