In this article we will discuss about the classification of psilophytopsida. The Psilophytopsida comprise of the fossilised ancient Silurian-Devonian order Psilophytales. The discovery of the different genera from such wide places as Canada, Scotland, Europe and Australia shows that these plants were of world-wide distribution in those days. The Psilophytopsida and the living Psilotopsida have been included within a single [...]
In this article we will discuss about the two principal types of stelar organisation in vascular plants: 1. Protostele 2. Siphonostele. Type # 1. Protostele: It is the simplest and most primitive type of stele. The vascular cylinder consists of solid core of xylem surrounded by phloem, pericycle and endodermis. There is no pith e.g., Selaginella, Lycopodium, Lygodium, Gleichenia etc. [...]
The following points highlight the nineteen essential features of ferns. 1. Ferns are seedless vascular plants of humid tropics and temperate areas. Some ferns live under sub-arctic conditions as well. 2. They constitute the largest living group of primitive vascular plants with over 10,000 species. Ferns once dominated the earth in carboniferous period (about 300 million years ago). 3. Plant [...]