New studies on the anatomy of the leal’, stem, stolon and root of 1 7 taxa of Gumma have revealed several interesting anatomical features. Scalariform perforation plates occur in most vessel elements of stolons and roots, although simple perforation plates are more frequent in the stems of large leafed‐species. The leaf surface and internal anatomy have not been studied since the late 19th and early 20th centuries. In this paper, detailed studies of the leaf include features such as marginal and laminar hydathodes. ‘warts’, hair types, and groups of 2 5 palisade‐like tells connected to each other by short communicating tubes. The anatomy of Gumma lierleri is described in detail for the first time. .Xostoc colonies in the leaf are illustrated.

An anatomical study of the leaves of 25 species belonging to 12 of the 19 genera has been made .The anatomical characters found to be of the most use in distinguishing taxa or groups of taxa are: in surface view-stomata1 outline. stomata1 density and distribution. subsidiary cell or surrounding cell patterns. presence /absence of hairs; in transverse sections-dimensions of adaxial epidermal cells. morphology of spongy mesophyll. midrib outline. number and distribution of vascular bundles. presencelabsence of an upper pulvinus. presencelabsence of sclereids in the upper pulvinus. presencelabsence of secretory sacs. crystal type and distribution .

Small diameter pyritized axes, commonly referred to as ‘twigs’, of fossil vitaceous and menispermaceous wood from the Lower Eocene, London Clay Formation of south‐east England are described here for the first time. The vitaceous twigs, which represent the earliest known occurrence of fossil Vitaceae wood, are characterized by large diameter, solitary vessels, tall wide rays which dilate in the phloem region, scalariform intervessel pits and simple perforation plates. The wood anatomy supports a close relationship to the Vitaceae and in particular the genus Rhoicissus Planch. The menispermaceous twigs are characterized by medium to moderately large vessels, simple perforation plates, alternate intervascular pitting and very broad and high rays. The anatomical characters support a close relationship to the Menispermaceae and in particular the genera Tinomiscium Miers and Coscinium Colebr. However, as these fossil twigs are not exactly similar to any particular genus they have been placed in the organ genus, Vitacexoylon Wheeler and LaPasha and Menispermoxylon Vozenin‐Serra, Privé‐Gill & Ginsburg, with which, respectively, they have the greatest similarity. These specimens were studied using reflected light‐ and scanning electron microscopy.

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The leaf teeth glands in four taxa from Salicaceae and six from 'Flacourtiaceae' were examined using both light and scanning electron microscopes. There appears to be a progression from glands of simple structure in the flacourtiaceous taxa and a tendency to a more complicated development in morphology and anatomy of the salicaceous species.