64 



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





Fig. 26 A-F Sciadopitynides greeboana sp. nov. A, apical portions of 

 leaves from Galley Hill. East Sussex, left to right V.64559. V.64560 

 (holotype). V.64561 (top row), V.64652. V.64563. V,64564 (bottom row). 

 V.64565, V.64566. V,64567, all x 2.5; B, upper half of leaf showing 

 maceration-resistant resin strands. V.64568. x 15; C, D, apical portions 

 of leaves from debris partings at Galley Hill, both x 15. C, with typically 

 broken leaf apex. V.64569; D, with less common intact leaf apex. 

 V.64570; E, lower portion of leaf showing tapering, untwisted, extreme 

 base of leaf. V.6457 1.x 1 5; F, central stomatal band of holotype (Fig. 

 26A, top row. middle) showing longitudinally arranged stomata with 

 prominent subsidiary cells. V.64560. x 100. 



files, not disturbed by stomata; usually four-sided, elongate, end 

 walls transverse or oblique, generally 20-150 |jm long x 8-19 |am 

 wide; anticlinal walls straight, 1—4 \xm wide; median longitudinal 

 ridge over outside of one or several cells in a file, alternatively, ridge 

 broken up into a row of small solid circular thickenings. Hypodermis 

 absent. Stomata longitudinally aligned and elongated, arranged in 

 longitudinal files; density 80-125 per mm- (average 92 per mm-). 

 Stomatal pit spindle-shaped, rim smooth; flanked on each side by 

 one, or rarely two, subsidiary cells with domed or thickened surface 

 walls; one subsidiary cell at each pole, indistinct from ordinary 

 epidermal cells. Encircling cells frequently present. Guard cells 

 slightly sunken; pair of dorsal plates 34—57 |jm long x 27-50 yon 

 wide, thickly cutinized, thinning slightly towards aperture, inner 

 anticlinal walls shallowly cutinized; polar appendages present but 

 variable in development; ventral plates very occasionally cutinized 

 adjacent to aperture. 



Name. After Greebo. Nanny Ogg's cat in the Discworld novels of 

 Terry Pratchett. 



Holotype & type locality. V.64560. Fig. 26A (middle top 

 row). F. A dispersed leaf fragment from Galley Hill. East Sussex. 

 Ashdown Beds Formation, Berriasian. 



Material and occurrence. Sciadopityoides greeboana sp. nov. 

 is known only from dispersed material in the English Wealden. It was 

 first recognised by Oldham ( 1976) from the Wessex Formation of 

 Worbarrow Bay. Dorset, and in the Ashdown Beds Formation at 

 Ecclesbourne Glen near Hastings and Galley Hill, East Sussex. It 

 was also found in Cuckfield No. 1 Borehole, Sussex. The species has 

 also been collected by Watson and co-workers from other debris 

 partings along the Hastings coastal section. Stratigraphical range; 

 Berriasian-Hauterivian. 



Description. The leaves of Sciadopityoides greeboana sp. nov. 

 are needle-like with a distinct median stomatal band on the lower 

 surface (Figs 26F; 27A-0), sometimes in a groove. The wide sto- 

 matal band accounts for one to two thirds of the total leaf-width. The 

 cuticle of the stomatal band is relatively thin and tends to be easily 

 damaged, so that in many specimens only the upper cuticle and the 

 stomatal-free edges of the lower cuticle are preserved intact. The leaf 

 is parallel-sided for much of its length, but tapers to an acute, slightly 

 asymmetrical, apex with the stomatal band pinching out to a point 

 just below the apex of the leaf (Fig. 27B, E, F, J, K). The extreme tip 

 of the leaf, however, is frequently missing (Figs 26C; 27B, E, J, K). 

 The leaf is slightly contracted at its base (Figs 26E, 27H) but the 

 width of the stomatal band remains the same; thus taking up almost 

 the entire width of the leaf in its basal part. The leaves often contain 

 two or three maceration-resistant strands, one down each side of the 

 stomatal band and usually a third along the midline (Figs 26 B; 27C- 

 G, M). These resinous strands, which are amber in colour and 

 fluoresce in ultraviolet light, are interpreted as the infillings of resin 

 canals. 



Both cuticles of this species are very brittle. The upper (adaxial) 

 cuticle is the thicker of the two and stomata are usually absent, 

 although an occasional stray one has been observed (Fig. 29A). The 

 ordinary epidermal cells, which form well defined longitudinal files, 

 are rectangular or square with thin, slightly sinuous outlines. At the 

 leaf base, however, the cells are much shoiter and have very wide 

 anticlinal walls which are strongly sinuous. Along the full length of 

 the leaf, the cells over the midline are clearly differentiated; being 

 distinctly narrower and more elongate than normal (Fig. 29A). 

 Throughout the upper epidermis, late-division cell pairs split by 

 longitudinal walls are common. The epidermal cells may have flat, 

 uniformly thickened surface walls but solid longitudinal ridges are 



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