LEAVES OF LIRIODENDROPSIS SIMPLEX (NEWB.) NEWB. FROM THE CRETACEOUS OF SIBERIA

Abstract

The biternate structure of leaves of Liriodendropsis simplex is proved on new original material. The individual variability of the leaflets is analyzed, and the systematics of available finds is revised. During the Cenomanian the species was a characteristic member of the subtropical floras of the Euro-Sinian Paleofloristic Region of North America and Eurasia and occupied a portion of warm temperate Siberian-Canadian and tropical Equatorial regions. In the Senonian the range of this genus was restricted to Greenland and the eastern coast of the United States.