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Ureae, are the commonest of all microbes and are present 

 everywhere. 



1.314. Root nodules and Nitragin. Nitragin is a sub- 

 stance made in Germany and protected by letters patent. It 

 consists of a jelly on which there has been sown minute orga- 

 nisms derived from the little warty growths or nodules, such 

 as are found in the roots of leguminous plants such as arahar, 

 dhaincha, sunn, ground-nut &c. It is manufactured and sold 

 by a chemical firm Meister, Lucius and Bruning, H6ehst-am- 

 Main, Germany in little bottles containing an ounce or two 

 of jelly, on the surface of which a white mould looking sub- 

 stance has been grown. It is claimed by the manufacturers 

 that this small speck of white fungus, if mixed with about 

 half a gallon of water, and the water sprinkled carefully over 

 about a cwt. of earth, and thoroughly mixed with it, is capable 

 of inoculating half an acre of land when spread over it as a 

 top-dressing, and that land so inoculated will in most cases 

 produce a much larger crop of clover, peas, beans, or other 

 leguminous plants, than uninoculated land. 



1.315. The root nodules of leguminous plants were first 

 discovered by the famous anatomist Malpighi about the year 

 1660. For two centuries no further notice was taken of them 

 until a Russian botanist Woronin made a careful microscopic 

 study of them. He described the root nodules in 1866 and 

 noticed that at a certain stage of their development they 

 were filled with a slimy matter containing myriads of tiny 

 little bright corpuscles capable of motion and resembling 

 bacteria, and he thought they were allied to Plasmodiphora 

 which caused the finger and toe in turnips. Professor Marshall 

 Ward classed the fungus as belonging to the genus ustilago 

 (smut in wheat being caused by a ustilago). De Fries in 1877 

 discovered that they were absorbers of N, as he found they 

 were full of albumen during the whole life of the plant until 

 about the time of the ripening of the seed in the host plant in 

 which is stored the albumen for the use of the future generation . 



