OBSERVATIONS ON ISOETES COROMANDELINA L. (fil)

The plants of Isoetes coromandelina L. (fil.) of Pratappur (Allahabad) population can be divided into three distinct categories on the basis of their megaspore structure and characters alone. The megaspores of all the plants are typically pustulate (tuberculate) but they conspicuously differ from one another in their diameter, size and the arrangement of pustules (tubercles) in addition to the apparent differences in their triradiate and equatorial ridges. The plants of this population might have originated either due to intrakaryotypic evolution, hybridization, or due to transmigration of some plants (or megaspores) from other populations in the vicinity of this population, thus rendering it to form a mixed population.