CLASSIFICATION. 



specialised or reduced forms. Sometimes a whole group of 

 families may be allied to a single family in another group, 

 yet it would be impossible iu a linear arrangement to show 

 this by the mere order of the families. As might be sup- 

 posed, it is often the families at the bases of the several 

 larger branches which show close affinities to the main trunk 

 and hence to one another, but these could not be placed next 

 to one another without at the same time severing the twips 

 from the branches. 



These difficulties have been partly obviated by indicating 

 supposed cross alliances of families or larger groups in 

 brackets after the name of the younger or both groups, where 

 one has had to be placed at a distance from its supposed 

 relative. 



DESCRIPTION OF CLASSES. 



The vegetable kingdom may be divided into five main 

 divisions, viz., Mycetozoa, Thallophyta, JBryophyta, Pterido- 

 phyta (these two sometimes united as the Archegoniata), and 

 Phanerogamia. Included in the large division of Thallo- 

 f>hy ta are the fungi, a group of importance to the f orester, 

 but not sufficient is known of the Chota Nagpur fungi to 

 include them in this flora, which is limited to a few of the 

 largest Pteridophyta, and to the Phanerogamia, or Flowering 

 Plants. 



Division— PTERIDOPHYTA. 



Class— Filicinae (Ferns). 



Stems rarely much branched, roots arising from them in 

 acropetal succession (or from the petioles). Leaves well 

 developed and of large size in proportion to the stem, often- 

 very compound, rolled inwards (circinate) when young, 

 Spores of one kind only (isosporous) , which produce 

 monoecious independent green protnallia, they (the eporesj 

 are formed in small roundish capsules (sporangia), which are 



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