type description from Republic, the complete nature of the fossil suite in the Allenby Formation allowed for more detailed examination of the relationships. Based on the details from the associated fossils Crane and Stockey placed B. leopoldae within Betula section Eubetula, subsection Costatae, near the living species Betula alleghaniensis. They noted that the last revision of Betula was undertaken by Winkler in 1904 and there were no reasons to conclude subsection Costatae was paraphyletic. Further revision of the genus was done by Forest et al in 2005, who found that subsection Costatae was paraphyletic based on molecular comparisons and the species in the subsection were grouped in the basal nodes of the genus phylogeny. B. leopoldae was interpreted as positioned either in the stem lineage of the genus, or as one of the grade of species which diverged early in Betula diversification. Crane and Stockey noted that the pollen preserved in the flowers is a close match for pollen morphotype Betula claripites that has been reported from the Princeton Basin and François Lake. Description Overall the leaves of B. leopoldae are elliptical to circular in outline ranging up to long, though averaging between . The leaf width is typically but ranges up to . The long petioles narrow from base to leaf blade and meet the blade at a symmetrical to asymmetrical base which may be cordate to obtuse. The margin is serrated with larger primary teeth that are separated by 7 or less smaller subsidiary teeth, all of which have a variable morphology from pointing apically to pointing basally. The teeth are non-glandular and each primary tooth is supplied by a secondary vein and each subsidiary tooth by a secondary vein branchlet. The leaves are pinnately veined with a thin midvein from which the secondary veins alternately or oppositely branch off between 40 – 80°. There are between 7 and 13 secondary veins that run parallel to each other and curve upwards near the tips before terminating in the teeth. As the secondaries approach the margin they produce up to 7 branches from the abaxial side, each of which supply subsidiary teeth. The tertiary veins are usually branching near the margin and less so not branching near the midvein. The quaternary veins fully extend between the tertiary veins with both branched and unbranched veins forming polygonal shaped areolae with veinlets terminating in them. The undersides of the leaves, the