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The megaspore membranes of Middle Jurassic Ginkgo yimaensis and Yimaia recurva are generally similar to each other in stratification. In this respect, they resemble also the megaspore membrane in mature ovules of Ginkgo biloba , but clearly differ from that of Cycas revoluta . The configuration of bacula in the patterned layer of mature ovules of both fossil and living ginkgos is essentially the same, while that of Yimaia recurva is slightly different. In Cycas revoluta , the patterned layer is quite differently constructed. Four developmental stages of the megaspore membranes of mature ovules of G. biloba are revealed by the present study. Considerable changes take place in the patterned layer, i.e. in the zonation and in the configuration of bacula, which appear to be mainly influenced by the diploid nucellus tissue rather than the haploid megaspore proper. The megaspore membrane in mature ovules of G. biloba appears to have developed structurally beyond that of G. yimaensis and may possibly be of peramorphosis origin.

A cladistic analysis of Mesozoic ginkgoaleans is made based on new evidence from the Middle Jurassic of Henan, China, together with previously known fossil records. Cordaites plus early conifers have been chosen as out-group for evaluating polarities of characters of ginkgoaleans. The analysis favours a monphyletic group of Ginkgoales including Trichopitys, Karkenia, Toretzia, Umaltolepis, Yimaia and Ginkgo. The most parsimonious cladogram shows that Ginkgo and Yimaia are phylogenetically closely related sister taxa and so are Toretzia and Umaltolepis, while Karkenia appears to represent a distinct evolutionary lineage of Ginkgoales in the Mesozoic. Based on the analysis, a provisional classification of Ginkgoales is proposed. The ovulate shoots of Trichopitys may be regarded as a putative archetype or its analogue from which various ovule-bearing organs of ginkgoaleans originated. All Mesozoic members are characterized by having short shoots and laminated leaves. The main evolutionary trends of vegetative parts in Ginkgoales are considered to be reduction of shoots and webbing and fusion of leaves. Their fertile shoots also tend towards reduction. Ovules become sessibe and reduced in number but increase in size through geological time.

A new species of the taxodiaceous genus Elatides, E. harrisii sp. nov., is described from the Lower Cretaceous of Liaoning, China. Its leafy shoots bear helically disposed, almost straight leaves with thin, epistomatic cuticles; the leaves are four-angled in transverse section and have a large resin duct. The female cone is terminal and is composed of dorsiventrally flattened cone scales with a long, acuminate, free distal end, the cuticles of which are essentially similar to those of the leaves. The ligule has a toothead distal margin. The seed is fragmentary; it has a thin outer cuticle of the integument and three cutinised layers inside the stone. There is a well developed pollen chamber and the apex of the nucellus forms a beak-like projection. The male cones are enclosed by bracts which resemble the leaves in cuticular structur. There are 4–5 pollen sacs per scale and the pollen grains are monoporate when well developed. Elatides harrisii is one of the most completely known species of Elatides so far described and is compared in detail with the European species. Other published occurrences of the genus in China are summarized and discussed.

An authigenic sideritic piece of secondary xylem resembling Protocupressinoxylon cupressoides (Holden) Eckhold from the Middle Jurassic of Yorkshire has been found in close association with Sewardiodendron laxum Florin in coeval deposits from Henan. Bored galleries are found in all three directions of the xylem. Some of them appear to be mended by parenchymatous tissue, while others are either empty or contain frass. Fecal pellets have two different sizes. Both are compact and composed of unidentifiable plant debris, and are believed to be produced by Coleoptera. This is the first fossil wood-boring record in China.

Fossil megaspore apparatuses of Azolla pinnata R. Brown are described from the late Quaternary of Zhejiang Province, East China. They prove to be identical in gross morphology and structure with those of the herbarium specimens of the same species. An electron microscopic study shows that the sporoderm ultrastructure is essentially constant in the megaspores of A. pinnata , either fossil or living, except those of some African specimens which have been considered by some authors as either a variety of this species or a distinct species. It is believed that the sporoderm ultrastructure will be found progressively useful in the taxonomic separation of Azolla species.