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Fossil seeds and seedlings of a Metasequoia-like taxodiaceous conifer occur in Paleocene deposits at the Munce's Hill and Gao Mine localities of central Alberta, Canada. Compression/impression specimens are preserved in upright growth positions among seedlings of the cercidiphyllaceous dicot Joffrea speirsii Crane & Stockey. There are a large number of seeds, a few of which were buried while germinating and show a radicle or short primary root. More than 500 Metasequoia-like seedlings have been identified that have two linear cotyledons with parallel margins and rounded tips. Three specimens have been found that display three cotyledons. Slightly older seedlings show decussate pairs of leaves attached to the stem distal to the cotyledons. Still older seedlings have axillary branches that show varying sizes and numbers of opposite leaves arranged in a single plane distal to the opposite pairs. These specimens reveal that both Joffrea and this extinct taxodiaceous conifer were early colonizers of North American floodplain communities at the beginning of the Tertiary. Key words: Metasequoia; Paleocene; seedlings; Taxodiaceae.

A permineralized Pityostrobus cone has been discovered in a calcareous concretion from shallow marine siltstones of Lower Cretaceous (uppermost Aptian; Clansenian) age in the Caucasus Mountains in southwestern Russia. Concretions of this type also contain wood fragments, gastropods, bivalves, and an extremely well-preserved assemblage of cephalopods. Russian spore and pollen analyses indicate that deposition in this region may have occurred during a temperate climate regime. The Russian cone is cylindrical, about 2.5 cm in diameter. Individual scales contain up to 17 resin canals and 18 vascular strands. Although the cone displays many pinaceous features, including inflated scale apexes, resin canals abaxial to vascular tissue in scale base, and scale strands curved on the adaxial side, the bract and scale trace are not united at their origin. Therefore, this cone is assignable to the genus Pityostrobus. Tunneled borings in the cortex of the cone axis are partially packed with numerous small frass (8.9 [[micro]meter]). These borings occurred prior to transport and deposition of the cone into the marine environment. The tunnels are up to 4.5 mm long, ca. 1 mm in diameter, and resemble those produced by modem cone boring beetles such as Conophthorus. This cone broadens our understanding of both the systematic diversity and paleoecology of Mesozoic Pinaceae.