ABSTRACT
The earliest vascular plants Earliest fossils of land plants, Cooksonia, occur in late Silurian rocks. It had photosynthetic stems but no leaves or roots and no stomata. By early Devonian several genera occur. They were low growing plants less than 50 cm high bearing sporangia at the tips (Rhyniopsida), laterally (Zosterophyllopsida) or in bunches (Psilophyton). Aglaophyton may provide a link with bryophytes.
