UP LOWER G KEENS ANU PL AXIS. 71 



Epidermis single-layered, with very thick cuticle. Stomates 

 apparently confined to grooves between the leaf-bases (?). 



HORIZON. Lower Grecnsaitd. 



LOCALITY. Luccomb Chine, Isle of Wight. 



FINDER. M. C. Stopes, 1912 (in situ). 



TYPE. Three slides from the same twig, V. 13230 and 

 V. 13230 b (British Museum, Nut. Hist.) and S B aa (Stopes 

 Coll.). 



DESCRIPTION. The type-specimen consists only of a minute 

 twig cut in three sections. 



This tiny plant-fragment had drifted into the locally decay- 

 ing tissue of a larger plant (see p. 247) with other more minute 

 and unrecognisable debris of vegetable cells, mineral granules, 

 etc. With it is also a small seed (see p. 249). It consists 

 of a central axis with secondary wood and six leaves sur- 

 rounding it, and it is so minute that from the outer epi- 

 dermis of one leaf to the outer epidermis of the leaf opposite, 

 thus including the central axis and two complete leaves, it 

 measures only 1-2 mm. The general contours and arrangement 

 of the axis and surrounding leaves are seen in PI. II, fig. 1. 

 The central axis consists of a pith surrounded by xylcm and 

 phloem ; and the cortex is merged entirely with the tissues of 

 the adpressed leaf-bases. In proportion to the size of the 

 central axis the leaves are large, though actually a single leaf 

 measures only about *5 rum. at its greatest width, Each leaf 

 contains a single relatively large resin-canal and a mass of 

 large-celled transfusion-tissue, which splits to form two groups, 

 one on either side of the canal. Large palisade-cells lie bcneatli 

 a hypodermic sclerenchyina-zone one or two cells wide, Tho 

 epidermal cells are well preserved, and appear to have an 

 enormously thick cuticle (see text-fig. 1(3, .). From the shape 

 and disposition of the tissues in the leaf, the morphologically 

 under surface is evidently plrysiologically the upper and exposed 

 one, indicating that the foliage was adpressed to the stem 

 except for the free tips. Stomata appear to have been present 

 only on the upper surface, in the grooves between adjacent 

 leaves, but this is not quite certain. This small adpressed 

 foliage is common in many Cupressineae, Taxodineir, etc., that 

 specific determination of such a vegetative twig can only be 

 attempted on a basis of the minutiae of its internal anatomy. 



