. Bulletin of the Natural Histort Museum. Geology series. . Fig. 30 A, B Sciadopityoides greehoana sp. nov. A, stoma viewed from the inside of the cuticle, , x 750. B, upper cuticle showing rectangular epidermal cells with median patches of thickening elongated longitudinally over one or more cells: thin sinuous outlines of hypodermal cells also shown, X 400. their inner and outer edges the guard cell anticlinal walls are shallowly cutinized (Figs 28A; 29F). Polar appendages are also a characteristic feature of this species but the extent to which they are developed is variable
. Bulletin of the Natural Histort Museum. Geology series. . Fig. 30 A, B Sciadopityoides greehoana sp. nov. A, stoma viewed from the inside of the cuticle, , x 750. B, upper cuticle showing rectangular epidermal cells with median patches of thickening elongated longitudinally over one or more cells: thin sinuous outlines of hypodermal cells also shown, X 400. their inner and outer edges the guard cell anticlinal walls are shallowly cutinized (Figs 28A; 29F). Polar appendages are also a characteristic feature of this species but the extent to which they are developed is variable (Figs 28A; 29F). The ventral guard cell wall may also be partially cutinized in some stomata (Fig. 29D, H). Discussion and comparison. When Oldham (1976: 460) first recorded the presence of this species in the English Wealden, he placed it tentatively in the Ginkgoales and remarked: 'this taxon is of ginkgoalean affinity but does not agree specifically with any of the published taxa". However, the single median stomatal band occur- ring in these leaves suggests to us that it is appropriately assigned to the coniferous form-genus Sciadopityoides Sveshnikova. Of course no affinity with the living genus Sciadopitys is inferred and the family affinities of Sciadopityoides greeboana sp. nov. remain un- certain. The leaves of S. greeboana are thought to have been spirally arranged on Sulcatocladus shoots which are described as a new species below. Attribution of the leaves of S. greeboana to shoots of Sulcatocladus is based on a constant association of the two species in the English Wealden and the strong similarities of their cuticles. Very similar shoots have been figured by Bose & Manum (1990, 1991) in association with Sciadopityoides-Vike leaves from the Lower Creta- ceous of West Greenland, Spitsbergen and Arcfic Canada. The leaves of 5. greeboana have many features in common with P. linkii: a high frequency of leaves with broken apices; a differentiated midline on the
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