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SynopsisTwo new species of petrified seedsEosperma edromense, andAnasperma burnensegen. et sp. nov. are described from the Cementstone Group of Berwickshire.Anaspermashows that the anatropous condition existed among Palæozoic ovules; it has a single integument with two lateral apical lobes.Rachides ofStauropteris berwickensissp. nov. and associated megasporangia are also described.An account is given of the theory of the telomic origin of the first ovular integument. The second (outer) integument in Angiosperm ovules may therefore have evolved after the establishment of anatropy, either from the first integument or as an overgrowth of the chalaza. Evidence is cited to support the theory that Angiosperm carpels have evolved from dorsiventral bivalved cupules.

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SynopsisThe Lower Carboniferous fossil Calymmatotheca kidstoni Calder is shown to be a simple seed and is redescribed under the new name Genomosperma kidstoni. A second species G. latens is also described. Genomosperma gen. nov. is of interest in possessing a free nucellus with a lagenostome and short salpinx. The nucellus is surrounded by an integument of about eight lobes which are free from one another and from the nucellus from near the base of the seed. The vascular details of t h e seeds have been studied and in each species pollen has been observed in the pollen chamber.Genomosperma is compared with various Pteridosperm seeds.

SynopsisTristichia ovensiis a Lower Carboniferous Pteridosperm known from both petrifactions and compressions. The stems possess a triradiate protostele and some show secondary xylem. The petioles have a butterfly-shaped trace and dichotomize repeatedly forming very slender axes sometimes bearing minute terminal pinnules similar to those ofMoresnetia zalesshyiStockmans. Associated withTristichiaare seeds and cupules ofStamnostoma huttonenseand less frequently compressions of seeds borne terminally on very fine dichotomous pedicels.