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A remarkably diverse Lower Cretaceous (Valanginian-Hauterivian) flora at Apple Bay, Vancouver Island, preserves seed plants at an important time of floristic evolutionary transition, about the same time as the earliest flowering plant megafossils. The fossils are permineralized in carbonate concretions and include tetrahedral seeds within cupule- or carpel-like structures. These enclosing structures, composed of elongate sclerenchyma cells with spiral thickenings that grade externally to a few layers of parenchyma, are vascularized by one collateral vascular bundle and lack trichornes. They apparently broke open to release the tightly enclosed seeds by valves. Seeds are similar to those of the Triassic seed fern Petriellaea, but arc about 100 million years younger and differ in size, vascularization, integumentary anatomy, seed attachment, and number of seeds/cupule. These new seeds ale described as Doylea zetrahedraspernia gen. et sp. nov., tentatively assigned to Corystospermales. Inverted cupules are reminiscent of an outer angiosperm integument rather than a carpel. Like fruits, cupules opened to release seeds at maturity, thereby foretelling several aspects of angiospermy. They show that nearly total ovule enclosure, a level of organization approaching angiospermy, was achieved by advanced seed ferns during the Mesozoic. [ABSTRACT FROM AUTHOR]

Large numbers of permineralized juglandaceous fruits were identified in calcareous nodules from the Eocene Appian Way locality on Vancouver Island, British Columbia, Canada. The fruits, small dorsiventrally flattened nutlets, 4.5–7.0 mm long and 5.5–9.0 × 3–5 mm in diameter, were studied using cellulose acetate peels. They are wingless, ribbed, and have a lobed epicarp that surrounds the hurler. Cells of the inner epicarp are thin-walled and traversed by a system of branching vascular strands. The stony nutlet wall is composed of fibers, with an outer layer of distinctive idioblasts. The fruits have a symmetry like that in Juglandaceae, subfamily Juglandoideae, tribe Platycaryeae, while the fibrous taut walls are like those of subfamily Engelhardioideae. This unique combination of characters indicates that these fruits represent a new genus and species of Juglandaceae: Beardia vancouverensis gen. et sp. nov. The excellent preservation of the Appian Way specimens has allowed a unique view of the internal fruit anatomy and external morphology. As the only wingless, flattened nuts known in the family, they further extend the range of morphological variation in fruits in the family. These fossils further support the hypothesis that North America was an important center of generic diversity for Juglandaceae during the early Tertiary. [ABSTRACT FROM AUTHOR]