REVISION OF THE ENGLISH WEALDEN FLORA 



been recognised amongst the dispersed cuticles collected by Watson 

 (for Watson 1969) and Oldham (for Oldham 1976) from the English 

 Wealden of Hastings and Galley Hill, East Sussex. Stratigraphic 

 range: Berriasian. 



Description. Fig. 34D clearly shows the longitudinal suture 

 between two decunent leaf bases as a groove. Fig. 34A. C shows the 

 suture on the left in a strong fold of cuticle. Fig. 34B has two sutures, 

 one extreme left and another splitting open on right. Fig. 34E shows 

 the rectangular outlines of the ordinary epidermal cells in longitudi- 

 nal files and the fine pitting on the outside surface is visible in Fig. 

 34F. The stomata are typically longitudinally aligned and restricted 

 to the areas adjacent to the sutures in Fig. 34D. Fig. 34F shows that 

 the stomatal pit is spindle-shaped, flanked on either side by a ridge 

 over the lateral subsidiary cells but with indistinct ends. Fig. 34H 

 reveals the elongate lateral subsidiary cells and a single, poorly 

 differentiated subsidiary cell at one pole. Only the dorsal walls of the 

 guard cells are cutinized in Fig. 34G, although the ventral walls too 

 are frequently cutinized in this species. 



Discussion. Sulcatocladus dibbleri sp. nov. has been attributed 

 to the needles of Sciadopityoides greeboana sp. nov. Although the 

 needles have not been found attached, the two are constantly 

 associated in the English Wealden and their cuficles are remark- 

 ably similar. Sulcatocladus dibbleri has rectangular epidermal cells 

 arranged in files with faint longitudinal ridges over the outside 

 surface, resembling those of the stomatal band in Sciadopityoides 

 greeboana. The stomata, also longitudinally aligned, have spindle- 

 shaped pits with smooth rims. One or two elongated subsidiary 

 cells flank the sides of the pit and polar subsidiary cells, when 

 present, are poorly differentiated. Guard cells too, are similarly 

 cutinized. The fact that the leaves of Sulcatocladus dibbleri have 

 never been found attached to the shoots of Sciadopityoides 

 greeboana may be indicative of a deciduous habit, as suggested by 

 Watson & Harrison (1998) and above for the very similar 

 Pseudotorellia linkiil Sulcatocladus robustus complex. The recon- 

 structed leafy shoot is envisaged as being similar to that of 

 Sulcatocladus robustus sp. nov. and Pseudotorellia linkii (Romer) 

 both for adult and juvenile foliage. 



Comparison. The cuticle of 5. dibbleri, at about 10 pm thick, is 

 much less robust than that of S. robustus which can be up to 50 pm 

 but otherwise the shoots are very similar in construction. S. 

 dibbleri and S. robustus are the only two species of the genus 

 Sulcatocladus Watson & Harrison to have been named but it seems 

 likely that some of the unnamed shoots associated with 

 Sciadopityoides, Pseudotorellia and similar leaves could be as- 

 signed to this genus. Rose & Manum (1991) have figured shoot 

 fragments found in association with Sciadopityoides nathorstii 

 (Halle) from the Lower Cretaceous of West Greenland. The leaf 

 scars on these shoots are distinctly round, as are the abscission 

 scars at the bases of S. nathorstii leaves (Hose & Manum 1990, 

 fig. 3) but it is not clear from the drawings whether there are 

 distinct sutures between leaf bases as in Sulcatocladus. However, 

 Manum & Rose (1990) have figured other shoots associated with 

 Sciadopityoides-Vike leaves in which the photographs (Rose & 

 Manum 1990, pi. 2, figs 4, 5) clearly show sutures between decur- 

 rent leaf bases exactly as in Sulcatocladus. Such shoots, of 

 undoubted coniferous affinity, being repeatedly found in associa- 

 tion with leaves of the Sciadopityoidcs/Pseudotorellia type, 

 suggests to us that we need to re-examine all leaves of this type 

 assigned to the Ginkgoales, particularly Pseudotorellia species, 

 with the question of associated shoots in mind. 



73 



? Family TAXACEAE 

 Genus TORREYITES Seward 



1919 Torreyites Seward: 419. [formal diagnosis not given] 



1920 Torreyites Seward; Seward & Sahni: 35. 



Type species. Tuwion carolinianum Rerry 1908: 383. figs 1-3. 



It should be noted that Seward misspelled Reny's specific epithet 

 carolinianum as carolianum (Seward 1919: 420) and this was re- 

 peated by Andrews ( 1 970: 216). 



Diagnosis. Needle-shaped or elliptical fossil leaves with 

 haplocheilic stomata confined to two well-marked longitudinal 

 grooves on lower surface; lacking prominent midrib on upper sur- 

 face of lamina. 



Remarks. The genus Torreyites was erected by Seward ( 1 9 1 9) for 

 Cretaceous and Tertiary fossil leaves referred to the modern genus 

 Torreya Arnott but for which he found the evidence unconvincing. 

 Seward did not formally diagnose the genus but applied it to the type 

 species Torreyites carolinianum (Rerry) Seward (1919: 420) and 

 listed several others for which neither cuticles nor seeds were 

 known. Since that time the genus has been little used and successive 

 authors (Florin 1958; Krassilov 1967, 1973; Harris 1979; Rose & 

 Manum 1990) have chosen to place fossil leaf species resembling 

 Torreya within the living genus, usually on the basis of cuticle 

 evidence alone. Given the lack of evidence from reproductive struc- 

 tures, we feel that Torreyites Seward remains a useful and more 

 appropriate genus, in particular for the extremely fragmentary 

 material dealt with in the present work. Its use does not imply the 

 possession of Torreya-\\V.Q ovules and the certainty of attribution to 

 the Family Taxaceae. Some fossil species are indeed close in cuticular 

 detail to modern Torreya and it is likely that they are closely related. 

 However, with only cuticular evidence there always remains a doubt 

 and it seems to us preferable to place them in a separate genus. We are 

 therefore returning to the use of the form-genus Torreyites as pro- 

 posed and used by Seward (Seward 1919; Seward & Sahni 1920). 



Torreyites detriti sp. nov. 



Figs 35^0 



1976 12 Cycad BeC Oldham (Code used instead of Linnean 



binomial): 450; pi. 61, figs 5-9. 

 1976 31 Taxod ScA Oldham (Code used instead of Linnean 



binomial): 462; pi. 73, figs 1-6. 



Diagnosis. Needle-shaped or elliptical leaf, 1-3 mm wide or 

 more, up to at least 15 mm long, with mucronate apex and base 

 without distinct petiole. Stomatal grooves on lower surface 70-210 

 \xm wide, about 500 \xm apart on either side of the midline; stomata 

 scattered within groove. 



Ordinary epidermal cells of upper surface 4-sided or irregular in 

 shape with more or less sinuous anticlinal walls, typically 30 ( 1 0-73) 

 |jm long and 26 ( 1 0-47) jjm wide; cells in median region elongate, 47 

 (20-78) |jm long and 17 (8-29) |jm wide, arranged in longitudinal 

 files. Outer surface often bearing thickened, longitudinal, cuticular 

 ridges; two continuous ridges along each file of cells. 



Ordinary epidermal cells of non-groove regions of lower surface 

 mostly 4-sided with straight or moderately sinuous anticlinal walls, 

 arranged in longitudinal files. Outer surface often bearing thickened, 

 longitudinal ridges similar to upper surface. Cells in median region 

 typically 44 (21-71) pm long and 17 (8-29) pm wide; cells in 

 marginal regions 36(1 8-65 )nm long and 19 (10-37) pm wide. Cell 

 files at edges of stomatal grooves more strongly ridged, bearing both 

 short round papillae and finger-like papillae up to 35 pm long or 

 more; sometimes fu.sed laterally to form cutini/ed fringe overhang- 

 ing stomatal groove. 



