Taeniopteris and other tree-fern like plants of the Permian period possessed simple leaves and bore small seeds along their edges near the base. Taeniopteris is associated with fossil reproductive material (seed-bearing leaves) given the name Crossozamia; these fossils resemble the modern- day reproductive megasporophylls of the genus Cycas, although they are more highly divided. A reduction in leaf size and the number of seeds could conceivably replicate the loose, open cone of this modern cycad. From the many variations of seed leaves, simple, and compound vegetative leaves, it is apparent that even in the Permian period early cycads and cycad-like plants were a very diverse group. For example, in Yuania chinensis from the Lower Permian of China, the lower pinnae were reduced to thorn-like structures similar to the prickles of the rachis of modern day Cycas. 

(At right) The leaves of the seed-fern, Gigantopteris, a useful index fossil of the Early Permian period, shade an early reptile, Captorhinus. Gigantopteris fossils have been found in both Asia and southern North America, indicating a wide distribution. The midrib and herringbone venation on the pinnate leaves (which have a superficial resemblance to the leaves of Stangeria) is easily distinguishable in even very small fragments of these fossilized leaves.