CERTAIN DICOTYLEDONOUS AND CONIFEROUS LEAVES. 245 
External Characters—Simple, ovate (see text-fig. 1), acuminate, tip 
blunt. Just below the apex the leaf widened to form a narrow “ shoulder ” 
on each side. Margin finely sinuate, with more prominently bluntly dentate 
teeth at intervals of about 11 mm. between the flat finely sinuate sinuses. 
Unicostate ; lateral veins paired, strongly marked, meeting the wide midrib 
at angle of 83°. Length 8:9 em., greatest width 5:2 em. 
TEXT-FIG. 1. 
Dicotylophyllum spiculatum. 
Cuticular Structure.—Fragments of this cuticle were extremely common 
in very many of the different lumps of the Bournemouth material. 
Under Epidermis (Pl. 20. figs. 5-8).—Under low powers of the microscope 
the unstained preparations show numerous roughly quadrangular grey 
patches, in the midst of each of which is a cruciform opening, the stoma. 
The quadrangular patches are parts of what are probably not guard cells 
but accessory cells which are packed with masses of structure apparently 
spicules, giving the appearance of heavy grey shading. The epidermal cells 
when examined with }-inch objective are seen to be thick-walled, irregular 
in size, and very asymmetric. The accessory cells which surround the pore 
