Q. Show Classification of englearn dPrantls system?
The outline and basis of classification of englearn d Prantl's system are given below:
1) Plant Kingdom has been divided, into XI11 Divisions but accdrding to recent modifications by Melchior (1964) the total Divisions are XVI.
2) Division I to XI1 dealing with Bacteria, different types of Algae, Fungi, Bryophytes, and Pteridophytes.
3) The XI11 Division is named as Embryophyta Siphonogamia; It is divided into 2 sub-division ased on the naked and^ enclosed ovules, that is
i) Gymnospermae (naked ovules)
ii) Angiospermae (enclosed ovules)
4) The sub-division Gymnospermae has been divided into 7 orders, the starting one being Cycadofilicales, the most primitive one where as the ending order is Gnetales, an advanced group of Gymnosperms.
5) The sub-division Angiospermae has been splitted into two
i) Monocotyledonae,
ii) Dicotyledonae
This division is mainly based on the striking differences between Monocots and Dicots such as the venation of leaf, 3-merous flowers in Monocots where as 4-5 merous flowers are present in Dicots.
6) Monocots are further divided into 11 Orders and 45 Families (14 Orders and 53 Families after the revision by Hans Melchior, 1964). The first or the starting Order is Pandanales which possesses naked, unisexual flowers with Typhaceae as the Starting family. The last order is Microspermae with orchidaceae as the last family.
7) Dicots are divided into 2 subclass namely:
i) Archichlamydeae, and
ii) Sympetalae
This division is mainly based on the condition of perianth, 1-seriate or 2- seriate and their fusion. For example, in Archichlamydeae the flowers may be naked or 1-seriate followed by 2-seriate condition but the petals are mostly free that is polypetalous condition. While in the case of syrnpetalae, as the name indicates, the petals are fused that is garnopetalous is found in this group.
8) Archichlamydeae has 33 Orders and 206 Families (37 Orders and 227 Families after the revision by Hans Melchior, 1964). The first or the starting order being Verticillatae and Casuarinaceae as the starting family, followed by some other order and fadilies without perianth or reduced perianth, then 1-seriate perianth and lastly Zseriate perianth. The last order being Umbelliflorae with Cornaceae as the last family.
9) Sympetalae which is also named as Metachlamydeae has 11 Orders in all with 52 Families (11 Orders and 64 Families after revision of Hans Melchior, 1964). The first or the starting Order being Ericales with Clethraceae as the starting family. The last or ending order of Sympetalae is Campanulales with Asteraceae or Compositae as the last or ending family and that is very rightly placed because this family is considered as the-highest evolved family among Dicot families.