Q. Describe the phylogenetic system of classification?
1) Hutchinson believed in Monophyletic origin of Angiosperms from a hypothetical group, which he' named, as Proangiosperms,
2) He tracedu2 main lines development of Dicots viz.
i) Lignosae (woody)
ii) Herbaceae (herbaceous)
3) Lignosae has 54 Orders and 251 Families. The starting order is Magnoliales with Magnoliaceae as the starting family passing through Annonales-Rosales-Malvales Rubiales and terminating at Verbenales with Phrymaceae as the terminating family.
4) Herbaceae has 28 Orders and 100 Families, The starting order is Ranales with Paeoniaceae as the starting family passing through rhoedales-Caryophyllales- Umbellales-Asterales and terminating at Lamiales with Lamiaceae (Labiatae as the ending family,
5) The haonocots have 29 Orders and 69 Families.
As a whole, Monocots have been subdivided into 3 distinct groups based on the nature of Perianth viz.
i) Calyciferae
ii) Corolliferae
iii) Glumiflorae
The starting order of Calyciferae is Butomales with Butomaceae as the starting family. The climax (ending) order is Zingiberales with Marantaceae as the ending . family.
The starting order of Corolliferae is Liliales with Liliaceae as the starting family. The terminating order of this group is Orchidales with Orchidaceae as the ending family.
In the case of Glumiflorae the starting order is Juncales and Juncaceae as starting family. The climax order is Graminales and Gramineae (Poacea) as the last or terminating family.