In this article we will discuss about the life cycle of selaginella, explained with the help of suitable diagrams. Selaginella is a very large genus of about 700 tropical to temperate species growing almost everywhere on this Earth. Although so large, the genus shows a uniformity lacking in the genus Lycopodium. The genus is more abundant in the tropical rain [...]
The following points highlight the four families under which marattidae has been classified. The families are:- 1. Angiopteridaceae 2. Marattiaceae 3. Christenseniaceae 4. Danaeaceae. Family # 1. Angiopteridaceae: Sporangia almost free, arranged in two rows on two sides of vein forming linear sori near margin. Genera: Angiopteris (100 spp. from Polynesia to Madagascar and the Himalayas), Archangiopteris (4 spp. from [...]
In this article we will discuss about the four orders under which primofilicidae has been classified. The orders are:- 1. Protopteridales 2. Coenopteridales 3. Cladoxylales 4. Archaeopteridales. Order # 1. Protopteridales: Protopteridium (Fig. 595A & B) from the Middle and Upper Devonian of Eastern Canada, Scotland, Belgium, Bohemia and China almost approaches the Psilophytales in simplicity with fern-like vegetative characters. [...]