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PLANTS CLASSIFIED 



individuals very much alike ; and the largest of which contains 

 very many groups of individuals, the groups having some char- 

 acters in common. This is called a system of classification. 



Classification of the Plant Kingdom. — The entire plant king- 

 dom has been divided into four sub-kingdoms by botanists : — 



1. Spermatophytes. 



Angiosperms, true flowering plants. 

 Gymnosperms, the pines and their allies. 



2. Ptendophytes. The fern plants and their allies. 



3. Bryophytes. The moss plants and their allies. 



Rockweed, a brown algse, showing its distribution on rocks below highwater mark. 



4. Thallophytes. The Thallophytes form two groups : the 

 Algse and the Fungi ; the algse being green, while the fungi have 

 no chlorophyll. 



The extent of the plant kingdom can only be hinted at ; each 

 year new species are added to the lists. There are about 110,000 

 species of flowering plants and nearly as many flowerless plants. 

 The latter consist of over 3500 species of fernlike plants, some 

 16,500 species of mosses, over 5600 lichens (plants consisting of a 



