THE BULB BOOK 



CLASSIFICATION OF BULBOUS AND 

 TUBEROUS PLANTS 



Scientists have divided the Vegetable Kingdom into five main 

 groups, viz. : — 



1. The Myxothallophytes. — These are organisms without green 

 colouring matter, consisting of naked masses of protoplasm or 

 Plasmodia. They are reproduced by spores from which arise swarm- 

 spores or myxamoebge. These again unite into plasmodia. The 

 best-known representative of this group is the Slime Fungus 

 (Plasmodiophora brassicce), which causes so much damage to the 

 roots of the Cabbage, Wallflower, and Stock tribes, and other 

 members of the natural order CruciferaB, by giving rise to the 

 disease known as " Club Eoot " and " Fingers and Toes." 



2. The Thallophytes. — These are plants which show no distinct 

 differentiation in tissue between roots, stems, shoots, and leaves. 

 They include the Blue-green Algae (Gyanophycece) ; the Bacteria 

 of various kinds; the Diatoms; the Green Algse (Chlorophycece); 

 the OonfervBe ; the Seaweeds ; and the Fungi. The last are im- 

 portant because of the numerous diseases which afflict the higher 

 plants; amongst them being the Potato disease, the mildew 

 of the Vine and Eose, the smut of Wheat, Oats, Barley, Eye, etc. 



The Fungi also include the cultivated Mushroom {Agaricus 

 campestris), the various "Toadstools" so-called, the Puff 

 Balls, etc., etc. 



A kind of intermediate or hybrid group between the Algse and 

 the Fungi is known as "Lichens." The Algse and Fungi live 

 together — the Fungus living upon the organic food which the 

 Alga obtains by means of its green colouring matter (chlorophyll) ; 

 and the Fungus in return secures moisture and the food dissolved 

 in it for its partner. This state of affairs is called "symbiosis," 

 and it appears that in Lichens the Fungus and the Alga could not 

 live without one another. 



3. The Bryophytes. — Here we have a distinct differentiation 

 into elementary stems and leaves. The best-known plants in this 

 group are the Mosses and Liverworts. 



4. The Pteridbpliytes. — These show a greater advance in 

 development, and roots, stems, leaves, and fructification are clearly 



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