Here is list of sixteen gymnospems:- 1. Cycas 2. Ginkgo 3. Pinus 4. Cupressus 5. Thuja 6. Juniperus 7. Cryptomeria 8. Podocarpus 9. Taxus 10. Cephalotaxus 11. Picea 12. Araucaria 13. Cedrus 14. Abies 15. Ephedra 16. Gnetum. 1. Cycas: Vegetative Structure: The plant is arboreal, un-branched palm tree like. The stem is columnar and also covered by an armour [...]
In this article we will discuss about the resemblances of gymnosperms with pteridophytes and angiosperms. Resemblances of Gymnosperms with Pteridophytes: 1. Plant body is sporophytic, and the sporophyte is differentiated into roots, stem and leaves in both gymnosperms and pteridophytes. 2. Members of both the groups show a regular alternation of sporophytic and gametophytic generations. 3. Cercinate vernation of the [...]
The following points highlight the five important fossil genera which have strengthen the concept of Progymnospermopsida. The fossil genera are: 1. Archaeopteris 2. Aneurophyton 3. Rellimia 4. Tetraxylopteris 5. Protopitys. Progymnospermopsida: Fossil Genera # 1. Archaeopteris: The frond-genus Archaeopteris of Pityales is known by about fifteen species, all of which had large fern-like fronds (Fig. 3.1 A). Beck (1960) has [...]