Revision Of The Early Oligocene Flora Of Hrazený Hill (Formerly Pirskenberg) In Knížecí Near Šluknov, North Bohemia Author Kvaček, Zlatko Charles University in Prague, Faculty of Science, Albertov 6, CZ - 128 43 Praha 2, the Czech Republic; e-mail: kvacek @ natur. cuni. cz; Author Teodoridis, Vasilis Charles University in Prague, Faculty of Education, Magdalény Rettigové 4, CZ - 116 39 Praha 1, the Czech Republic; e-mail: vasilis. teodoridis @ pedf. cuni. cz; Author Zajícová, Jana Charles University in Prague, Faculty of Science, Albertov 6, CZ - 128 43 Praha 2, the Czech Republic; e-mail: jana. zajicova @ natur. cuni. cz. text Acta Musei Nationalis Pragae Series B 2015 2015-10-31 71 1 - 2 55 102 http://dx.doi.org/10.14446/amnp.2015.55 journal article 10.14446/AMNP.2015.55 2533-4069 13182943 Populus zaddachii HEER Pl. 17, Fig. 4–6 1859 Populus zaddachii HEER , p. 307 1869 Populus zaddachii HEER ; Heer, p. 30, pl. 5, pl. 6, fig. 1–7, pl. 12, fig. 1c. 1961 Populus zaddachii HEER ; Knobloch, p. 254, pl. 12, fig. 9, pl. 13, fig. 5, pl. 14, fig. 2, 7. According to Knobloch (1958 , translated from Czech), the leaves are broadly ovate elongate to cordate with crenulate-serrate margin, at base rounded to slightly cordate; the midrib is straight extending into a flattened petiole up to 2 mm broad and accompanied by two lateral primaries, from which thin secondary veins arise. They attain a size ranging from 36 mm to more than 120 mm in length and 29–73 mm in width. D i s c u s s i o n. Knobloch (1961 , p. 254) stressed the large variation in leaf morphology of P. zaddachii and compared it with the living P. balsamifera L. This fossil species typical of the European Oligocene (see Mai and Walther 1978 ) is known from several other Oligocene sites in North Bohemia and Saxony (see Walther and Kvaček 2007 ). M a t e r i a l s t u d i e d: Leaf impressions, NM-G2990, NM-G2991, NM-G8578, NM-G8579a, b, NM-G8590, NM-G8604a, b, EK 359.