Kalmia” elliptica R. W. BROWN

Manchester, Steven R., 2014, Revisions To Roland Brown’S North American Paleocene Flora, Acta Musei Nationalis Pragae Series B 70 (3 - 4), pp. 153-210 : 176

“ Kalmia” elliptica R. W. BROWN

This species is represented by elliptic leaves with entire margins, and pinnate secondaries that arise decurrently from the midvein. Hickey (1977) considered the attribution to Ericaceae likely to be correct, based on several apparently unique leaf architectural characters.

Cornales

The order Cornales was particularly well represented in the Paleocene of the Rocky Mountains and Great Plains region. Examples include Cornus (already recognized by Brown 1962), Davidia , Amersinia /Beringiaphyllum (previously treated as Viburnum ), and Browniea (previously treated as Eucommia ). At some sites one or more of the latter three genera are dominants of the community. Pollen of Nyssapollenites thompsonianus THIERGART ex POTONIE and Cornus sp. are known from Almont, North Dakota ( Zetter et al. 2011).

Cornus swingii MANCHESTER, XIANG, KODRUL et AKHMETIEV

Brown (1962) recognized two species of dogwoods: Cornus hyperborea HEER , and C. nebrascensis SCHIMPER. However , the holotype of C. nebrascensis SCHIMPER (= C. acuminata NEWBERRY and C. newberryi HOLLICK ) has marginal teeth ( Brown 1962; Johnson 2002), unlike any extant Cornus , lacks the distinctive double-armed trichome impressions expected for Cornus (Manchester et al. 2009), and now serves as the basis for a new extinct genus, Mciveraephyllum , established here on p. 178. Additionally, the lectotype of Cornus hyperborea HEER , from the Paleocene of Greenland, might be Cornus , but other affinities, e.g., to Lauraceae , cannot be ruled out because it lacks impressions of the diagnostic compass-needle like trichomes. In order to accommodate leaves from the Paleocene of Wyoming, Montana and North Dakota that could be placed with confidence in Cornus , due to the preservation of their distinctive trichomes, Manchester et al. (2009) established a new binomial, Cornus swingii . The fruits produced by Cornus swingii remain unknown, but anatomically preserved fruits of Cornus subgenus Cornus have been described from the Paleocene of North Dakota (Manchester et al. 2010) as Cornus piggae .