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In addition to having a rich assemblage of mammalian fossils, the Gao Mine locality in the Paskapoo Formation of south-central Alberta has yielded numerous plant specimens of late Paleocene (late Tiffanian or Ti5) age. The plant fossils are preserved in siltstones and fine-grained sandstones interpreted as overbank sediments that were deposited on an aggrading floodplain. The assemblage is dominated by the cupressaceous conifer Metasequoia foxii and the cercidiphyllaceous dicot Joffrea speirsiae, including their well-preserved seedlings. The flora also contains foliage of the ferns Onoclea and Speirseopteris and the woody dicots Palaeocarpinus, Aphananthe/Celtis, Aesculus, Beringiaphyllum, ?Trochodendron, and Wardiaphyllum, as well as seedlings of unknown dicotyledonous angiosperms. Metasequoia foxii and Speirseopteris are unique to the floras of Gao Mine and the nearby Munce's Hill site (Tiffanian Ti4). The remainder of the taxa are common in late Paleocene floras of North Dakota, Montana, and Wyoming, all USA. The floras of the nearby Joffre Bridge Roadcut and Blindman River sites (both Tiffanian Ti3) are more diverse, but both of those sites encompass a wider range of depositional environments and may include higher percentages of allochthonous material. Most of the Gao Mine material is autochthonous. The seedlings were buried in place, along with the surrounding leaf litter, preserving a record of the local plant community. En plus d'un riche assemblage de fossiles mammaliens, la localite de Gao Mine de la Formation de Paskapoo du centre-sud de l'Alberta a produit de nombreux specimens de plante d'age paleocene tardif (Tiffanien tardif ou Ti5). Les fossiles de plantes sont preserves dans des siltstones et des gres a grains fins interpretes comme etant des sediments de debordement deposes dans une plaine alluviale inondable. L'assemblage est domine par le conifere cupressace Metasequoia foxii et la dicotyledone cercidiphyllacee Joffrea speirsiae, incluant des semis bien preserves de ces especes. La flore contient egalement des frondes des fougeres Onoclea et Speirseopteris, les dicotyledones ligneuses Palaeocarpinus, Aphananthe/Celtis, Aesculus, Beringiaphyllum,?Trochodendron et Wardiaphyllum, ainsi que des semis d'angiospermes de dicotyledones inconnues. Metasequoia foxii et Speirseopteris ne sont presents que dans les flores de Gao Mine et du site avoisinant de Munce's Hill (Tiffanien Ti4). Les autres taxons sont repandus dans les flores du Paleocene tardif du Dakota du Nord, du Montana et du Wyoming (tous aux Etats-Unis). Si les flores des localites avoisinantes de la tranchee routiere de Joffre Bridge et de Blindman River (toutes deux d'age Tiffanien Ti3) sont plus variees, ces deux sites englobent un plus grand eventail de milieux sedimentaires et pourraient contenir des proportions plus elevees de materiel allochtone. La majeure partie du materiel de Gao Mine est autochtone. Les semis ont ete ensevelis en place, ainsi que les feuilles mortes les entourant, preservant ainsi un registre de la communaute vegetale locale. [Traduit par la Redaction], Introduction In 1988, R.C. Fox and K.Q. Gao discovered vertebrate fossils at the Gao Mine locality in the Paskapoo Formation near Red Deer, Alberta, Canada, and quarrying at the site [...]

Abstract: A diverse assemblage of fossil conifer leaves was identified in calcareous marine concretions from the Lower Cretaceous (Valanginian-Hauterivian) Apple Bay locality, Vancouver Island. Of the hundreds of isolated leaf [...]

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 x 3-5 mm in diameter, were studied using cellulose acetate peels. They are wingless, ribbed, and have a lobed epicarp that surrounds the nutlet. 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 nut 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 genetic diversity for Juglandaceae during the early Tertiary. Key words: Appian Way; Beardia, Engelhardioideae, Eocene, fossil, fruits, Juglandaceae, Platycaryeae.