BACTERIA IX AaUICVLTVUE. 335 



r?c it known that wc, Fiicdiich Xohlic and Lorcn/. Ilillncr, of Tliarand, 

 pared for tiausporl in lliiid ciiltuics. 'J'lio colonies in the ajjar-jielatin are dis- 

 inocuiation of -oil for the cultivation of leguminous ])laiits and we do hereby 

 declare the following to be a clear and exact description of the invention: 



Since the function of the root nodules or tubercles of the Leguniinosfe in 

 the supply of nitrogen to these ])lants has been discovered by the fundamental 

 researches of Ilellriegel we have been woiking on this problem f(jr a number 

 of years, and have examined more especially the bacteria in said nodules or 

 tubercles (first identified and isolated in cultures by Beyerinck) in order to 

 determine the relationship between the bacteria and the reception of the free 

 unt'ombineil nitrogen of the air in the soil by the various kinds of Leguminosae. 

 These researches have resulted, in the first place, in the confirmation of the at 

 that time still disputed fact that the introduction of these bacteria into the soil 

 produces, without exception, in soil free from these bacteria, the root nodules 

 or tubercles on the plants in question having papilionaceous flowers and enables 

 these plants to assimilate the free nitrogen. A soil inoculated with these bac- 

 teria, even when it contains absolutely no nitrogen in an assimilable form so 

 that the plants without any such inoculation would starve, enables the 

 Leguminosa? to produce as rich a yield of dry material and nitrogen as they 

 would otherwise produce if grown in a richly manured soil containing much 

 assimilable nitrogen. 



It has been established by us as an entirely new fact that the tubercle 

 bacteria of the various Papilionacea? are of full strength ((. e., in the production 

 of ellicient nodules or tubercles) only in that species (of leguminous plant) 

 from whose root tubercles they weie themselves obtained. With closely allied 

 sjjecies they are of less strength and with systematically different species they 

 are useless or inactive. Bacteria cultures from pea roots, for example, are 

 quite useless for Rohinia plants, while they promote the growth of peas in a 

 very energetic manner, and that of the allied vetches somewhat more feebly; 

 on the other hand, the bacteria from Rohinia nodules or tubercles are quite 

 efficient with Rohinia plants, but in a lesser degree with Cohitea, and are abso- 

 lutely useless with j^eas. 



At first sight it might possibly be thought that the production, transport, 

 and distribution of such large masses of crude inoculating material as would 

 appear to be necessary for the sufficient impregnation or treatment of large 

 areas of land would be very difficult and costly, and therefore not practicable, 

 while there would also be the danger that in the crude inoculating material, 

 besides the active bacteria of the root nodules or tubercles, there would be car- 

 ried from field to field, at the same time, microscopic organisms which would be 

 detrimental to growth and would interfere more or less with the action of the 

 inoculating material. Our process is, however, free from any such objections 

 as those above mentioned, inasmuch as bacteria bred in quantities directly from 

 the nodules or tubercles of the Leguminosae in pure cultures are used as the 

 inoculating material. Farmers are, therefore, placed in a position to make 

 land, which was unfruitful by reason of its lack of nitrogen, fit for the culti- 

 vation of fodder and other plants belonging to the order of the Leguminosse 

 and to insure and increase the yield of soil. This inoculation has, moreover, 

 an essential practical bearing in connection with the so-called ' green manuring.' 



Our process of inoculating land with tubercle bacteria is to be carried out ' 

 as follows: The active bacteria to promote the growth of the Leguniinoste are 

 delivered to the farmer in glass tubes or other suitable packages, which contain 

 pure colonies thereof in agar-gelatin having suitable additions for propagating 

 such bacteria, for instance sugar, asparagin and an aqueous extract of the green 



