New phylogenetic facts on fossil spores

New data are given concerning the strata of the spore coat. It is possible to count the strata, but often the spore-coat strata of different plant families cannot be put in morphological relationships. A rule is found in the phylogenetic evolution of the saccus. In fossil spores no prothallium is seen. Proximal germination at the tetrad scar has occurred for a longer time than was believed (cf. the Cycadofilicales, in part the Cycadeoidales, and perhaps the Coniferales).