gymnospermous

The pollen that they produce is strictly known as pre-pollen, as it germinated proximally and was thus intermediate in structure between pteridophytic spores and gymnospermous true-pollen.

In contrast, another of his scientific ideas has been disproven by later modern research - the idea of a direct ancestry of the centrosperms (approximately equal to Caryophyllales) from the gymnospermous Gnetophyta and, hence, two separate evolutionary lineages within the flowering plants.