Columnar unbranched stems bear a crown Gymnosperm
The sporophyte alternates with the gametophyte to complete the life cycle. Classification of Gymnosperm : Chamberlain (1935), in his book Gymnosperms Structure and Evolution, has divided Gymnosperms into two divisions. They are Cycadophyta and Coniferophyta. directly divided into three orders.
The Cycadophyta is namely Cycadofilicales, Bennettitales and Cycadales. The division Coniferophyta is divided into four orders. They are Cordaitales, Ginkgoales, Coniferales and Gnetales. Each and every order is divided into families, genera and species.
Seeds were formed on normal or specialised stem and a crown of cycad-like leaves. The wood was This division includes fossils and living forms. It is members alone. They were common in the late Palaeozoic Bennettitales and Cycadales. The first order includes fossil divided into three orders, namely Cycadofilicales, Division I. Cycadophyta : era, which is known as the age of 'fossil Cycads', The plant body is differentiated into a stout tu monoxylic, ie. loose and soft Reproductive structures are produced in definite cones.
The order Cycadales includes living species. The living Cycades are palm-like trees. They have columnar unbranched stems bear a crown of pinnately compound leaves at the apex wood is manoxylic.
The reproductive structures are usually borne in the plant is dioecious. Sperms are motile. Spores were formed in sporangia which were aggregated in groups to form synangia.
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