ON THE GROWTH OF LEGUMINOUS CROPS. 13 



necessary for the formation of the non-nitrogenous substances. The 

 view does not, however, assume that nitrogen is eliminated from the 

 plant in the process, and so lost. 



Then, again, plants such as many of the Leguminosse, which are 

 characterised by assimilating relatively very large amounts of nitrogen 

 over a given area of land, and by the formation of very large amounts 

 of proteid in proportion to plant surface, produce relatively small 

 amounts of the carbohydrates. 



Nor is it irrelevant to refer to the fact that, from theoretical consi- 

 derations, it was for many years assumed, especially in Germany, in 

 opposition to the teachings of our own numerous direct experiments, 

 that in the animal body the non-nitrogenous substance fat was 

 mostly, if not always, produced by the degradation of proteid ; the 

 nitrogenous bye-products being for the most part, if not entirely, 

 eliminated from the body as waste matter. It is, however, now 

 indubitably established, at any rate in the cases of the herlivora which 

 produce the most fat, that that substance is derived largely, if not 

 exclusively, from the non-nitrogenous constituents of the food the 

 carbohydrates. 



In the case of the supposed transformation in plants, the same 

 prodigal expenditure of the nitrogenous bodies in the formation of the 

 non-nitrogenous is, however, as has been said, not involved. 



EFFECTS OF NITROGENOUS MANURES ON LEGUMINOUS CROPS. 



Such are the very marked effects of nitrogenous manures in 

 increasing the amounts of produce, and especially in increasing the 

 production of non-nitrogenous constituents, when applied to our non- 

 Leguminous, and comparatively low in nitrogen, crops. I have now to 

 illustrate the influence of nitrogenous manures on various Leguminous 

 crops, which, on the other hand, are characterised by containing a 

 high percentage of nitrogen in their dry substance, and by assimilating 

 a large amount of nitrogen from some source over a given area of land. 

 It will be seen that the results to which I have to direct attention will 

 bring to view some very remarkable failures, but also some not less 

 signal and significant successes. 



My first illustrations relate to experiments with Beans, grown for 

 many years in succession on the same land without manure, with a 

 purely mineral manure (consisting of superphosphate of lime, and salts 

 of potash, soda, and magnesia), also with the same mineral manure, 

 and nitrogenous manure ia addition, supplied either as ammonium- 

 salts, or as sodium-nitrate. The results are recorded in Table VI. 

 (p. 14). 



It is seen that the record relates to a period of 32 years of continued 

 or interrupted experiment with Beans, from 1847 to 1878 inclusive. 



The first three columns show the produce of the corn, the second 

 three that of the straw, and the third three that of the total produce, 

 corn and straw together ; each under three conditions as to manuring. 



