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Sir J. B. Lawes and Prof. J. H. Gilbert. [Jan. 9, 



stouter main root than any of those in the other pots. From the 

 side branches there proceeded a large amount of fine root-fibres, 

 which extended throughout the whole soil, those from the different 

 plants being much interwoven. The roots extended round the sides 

 and along the bottom of the pot, much more than in either of the 

 other pots. A photograph was, therefore, taken of the block of soil 

 as it came out of the pot, showing this special character of root- 

 development. There were three small clusters of nodules on the 

 roots of each of the three plants, one or two smaller bunches, and 

 here and there a single nodule. But the clusters were much smaller, 

 the total number of nodules was much less, and they were more 

 distributed throughout the soil, in this pot with rich garden soil, than 

 in either of the others, even than in pot 1, without any soil-extract 

 seeding. As the description shows, the root-development was at the 

 same time much greater than in either of the other pots. To this 

 point we shall have to recur again, but it may be remarked in passing, 

 that the greater development of root and root-fibre, and the 

 less development of the root-nodules, in the soil which itself supplied 

 abundance of nitrogenous, as well as of other nutriment, is 

 consistent with the observations of some other experimenters ; but 

 it is, on the other hand, inconsistent with the observations and views 

 of others. 



Finally in regard to the relative development of root-nodules under 

 the different conditions, the evidence is clear, that there was a greatly 

 enhanced development of them under the influence of the soil-extract 

 seeding ; and that, coincidently with this, there was a considerably 

 increased growth of the above-ground parts of the plant. 



The distinctly less development of root-nodules in the rich garden 

 soil, than in the sand with soil-extract seeding, as observed in the 

 case of the peas, was, however, not found in that of the lupins, as 

 the following notes on the roots of the lupins grown in 1888, will 

 show. 



In pot 5, with the impure yellow sand, but without soil-extract, 

 eventually three plants of blue lupins grew. From the short, thick, 

 main root, many branches proceeded, extending from the top to the 

 bottom of the soil; those plants having the largest above-ground 

 development had also the most root. The branches were fleshy and 

 succulent, and thicker at a distance from the main stem than near 

 it. No nodules were observed on the roots in this pot. 



In pot 6, with lupin-soil-extract, but with only two plants, the roots 

 were of the same general character as to branching, extension, fleshi- 

 ness, and succulence, as those in pot 5. There was, however, one 

 nodule, about the size of a pea, on a root-fibre on one of the two 

 plants. 



In pot 7, with ihe lupin sand itself, there was no plant. 



