Cycas, a small-sized tropical gymnosperm is a dioecious plant. In this microsporophyll are organized to form male cones are present on one plant and megasporophylls are organized on a different plant. Thus, male and female plants are different in Cycas. Roots in Cycas have small specialised roots called coralloid roots are associated with N2 - fixing cyanobacteria. The stems are unbranched. Pinnate leaves persist for a few years.