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the vegetable kingdom, and whicli possibly to you may have no interest 

 whatever. For myself, I entered on their study at the suggestion of 

 my chief, Dr. Selvvyn, Director of the Geological and Natural History 

 Survey, and now, when I stand only at the portal of the vast unex- 

 plored region beyond, I ask your attention to a few of the facts ah-eady 

 gleaned, and hope they may not be altogether without interest, and 

 even profit. 



At present the greater number of systematic botanists recognize 

 five great divisions or classes in the vegetable kingdom, of which the 

 fifth or lowest is named thallogens or thallophytes, because organisms 

 of this class instead of growing upright expand into a thallus consist- 

 ing of parenchyma alone, and never exhibiting a marked distinction 

 into root, stem and foliage. All plants of this class are flowerless» 

 This class includes five orders, 'viz. : 



Lichens. 



Fungi. 



Alg^. 



DfiSMiDiACEiE, single cells of a green colour, found in fresh water. 



DiATOMACE^, single cells of brown colour, and having silicious 

 cell walls, found in sea and fresh water. 



The plants in the first order, lichens, are never aquatic, but grow 

 on bark of trees, earth or rock, and draw their nourishment from the 

 air. Fungi, on the other hand, are parasitic, and live by appropriating 

 the juices of living plants to their own use or the organized matter of 

 dead and decaying animal or vegetable. Algse are almost strictly aquatic, 

 the greater number of them being seaweeds. You will note that these 

 three orders, although quite closely related, are kept apart by their 

 special modes of obtaining nourishment, and that the fungi always use 

 prepared food even if by so doing they destroy that which man has 

 laid up for himself Those species which produce rust, smut, mildew 

 and many other plant diseases are parasitic and prey exclusively on 

 living plants, while mushi-ooms (agarics) and puff-balls live on dead 

 and decaying matter. 



A s the purpose of this paper is not to give the classifications of 

 the order,' I shall pass at once to the section named the Agaricini, as it 



