MORPHOLOGY, TAXONOMY, STRATIGRAPHY, AND GEOGRAPHICAL DISTRIBUTION OF DEVONIAN ARHAEOPERISACCUS
Tudy of morphology and ultrastructure of sporoderm of some Archaeoperisaccus (Naumova) P otonie has shown that this genus combines dispersed miospores of different botanical origin. Two groups of miospores can be distinguished in its composition. To the first group belong miospores produced by plants closely related to archaeopteris plants, to the second– those produced by lycopsides. The identified heterogeneity of Archaeoperisaccus genus changes our concepts of its stratigraphic range and geographical distribution.