Cordaites is an extinct genus of seed plants from the Pennsylvanian Period that are thought to be closely related to conifers. They grew in a variety of habitats from mangrove-like environments to the dry hinterlands. Most, however, grew on floodplains or in swamps. The reproductive structures were similar to the early conifers with which they co-existed. The reproductive structures consisted of a short shoot borne in a leaf axil at the junction of the leaf stem with a branch. The shoot had a series of leaves with each leaf holding a secondary shoot within a smaller axil. Pollen sacs and ovules were present in these smaller axils. Like many conifers, the pollen of the plant had a central portion surrounded by a bladder that helped to make the large grain buoyant in the air.