In this article we will discuss about the external features and internal structure of calamites. External Features of Calamites: The calamitean fossils range from pith casts, stems, twigs and leaves to strobili. The stem is known as Calamities, leafy twigs are called An nularia, and fructification is known as Calamostachys. The plant body of Calamites was a tall tree (Fig. [...]
In this article we will discuss about:- 1. Habit of Lepidodendron 2. Internal Structure of Lepidodendron 3. Reproduction. Habit of Lepidodendron: Like other ancient lycopods, Lepidodendron was also tree like in habit (Fig.55). In general appearance it was not unlike that of present day Lycopodium. But in size the genus enormously exceeded the herbaceous Lycopodium. The petrified trunks were sometimes [...]
After reading this article we will learn about:- 1. Sporophyte of Azolla 2. Gametophyte of Azolla 3. Phylogeny. Sporophyte of Azolla: The sporophyte is extremely small when compared with Marsilea and Salvinia. It is distinguishable into stem, leaves and roots. The stem is often called the rhizome. It is profusely branched and on its upper surface is covered with dense [...]