and "soil-inoculated" crops. The amounts of nitrogen present are in proportion to the total yield of crop. We may, therefore, safely conclude that Nitragin had exerted a decidedly beneficial influence, and that the increase of growth and nitrogen assimilation shown in the foregoing data are fairly traceable to its action.

The plants in all the pots appeared healthy, but those in the inoculated soil were decidedly larger and more robust than the others. It was also noticed that the root systems of the untreated plants were meagre and poorly supplied with nodules when compared with those of the treated plants, more especially with those on the plants growing in the inoculated soil.

The figures of Table VII. show that the percentage of nitrogen is not larger in the plants from inoculated soil or seed than in those untreated, we must conclude, therefore, as in the case of the clover and of the peas, that the additional nitrogen in the treated crop is due to the greater development of root or foliage, or both, induced by the Nitragin.

In 1898 the results, both from the pot and plot trials, were somewhat unsatisfactory, and seemed to indicate that the vitality of the culture, through the action of time, light or warmth, had been impaired. In the pot trials, the largest crop was from the "soil inoculated " plants; the smallest from the "seed inoculated." The amounts of nitrogen were practically the same in the untreated and "soil inoculated" plants, and slightly higher than in the "seed inoculated" plants.

In the plot trials the seed was sown June 13th and the plants allowed to grow until October 10th. The figures obtained are as follows :

These give further evidence that the Nitragin was, in the case of the beans, ineffective, due probably to one of the causes already referred to.

Reviewing this work, it will be seen that the results are, with the exception of the last recorded experiment, eminently satisfactory, furnishing evidence of a marked character as to the value of this inoculating agent. The experiments with clover Nitragin and pea Nitragin have invariably given higher yields for treated plants, as against those grown in similar soil and under like conditions, but not treated with Nitragin. With horse beans, in 1898, we failed to obtain results that would decisively show a benefit from inoculation, but in the season previous a noticeable increase followed inoculation, pointing therefore to a deterioration of the particular sample of the preparation used in that year rather than to its general uselessness. There seems indeed no doubt from these data but that when fresh Nitragin is employed we are furnishing the legumes

with bacteria of unimpaired vitality that will enable them, under favourable conditions of soil as regards moisture, warmth, and a supply of mineral food, to assimilate free nitrogen.

The vitality of these germs, however, when they are not in their natural habitat is precarious. It appears that they are particularly susceptible to a temperature above 100° F. and to strong light. Moreover, their life in the preparation (Nitragin) cannot be guaranteed for more than six weeks from date of preparation, even under the most favourable conditions as regards light and heat. It is a general character of bacterial preparations that they must be fresh to ensure their satisfactory operation. For this reason it is extremely doubtful if Nitragin will ever come into general use by farmers, and we suppose it is on account of these difficulties that, as we have learnt within the past month, the German manufacturers have abandoned its preparation.

But whether the use of Nitragin ever becomes common or not, results such as are recorded in this paper will be of value, for they furnish evidence of the strongest character that the growth of certain of the legumes at least may be materially increased by inoculating the seed or soil with these nodule bacteria. If it were found that any district would not furnish luxuriant crops of clover by reason of the absence of these organisms, the way is now open to overcome the difficulty. Such instances of failure in obtaining a good crop of clover in the neighbourhood of Ottawa, as have come under our notice, appear, however, to have been due rather to deficiency of moisture, as in a season of drought, or to an unsuitable condition of the soil. The general presence of root nodules in this vicinity leads us to believe that these special nitrogen assimilating germs are by no means scarce in this district.

In several of the Western States of America inoculation has been practised by taking soil from a field that has previously grown a good crop of clover and scattering it broadcast over the area about to be sown. Excellent results from such work at several of the Experimental Stations have been recorded. The plan is extremely simple for those who can procure such soil, and could be easily carried out by farmers. Another modification of this method of inoculation would be to pour a quantity of cold water over the soil rich in germs, stir well and use the supernatant water for inoculating the seed to be sown.

Experiments conducted on the Experimental Farm, Ottawa, during the last five years have shown that clover is one of the most economical fertilizers with which impoverished land can be recuperated, even when the roots only are allowed to decompose in the soil. We are, therefore, justified in considering any method which may be used to encourage its growth as one of great importance and value to agriculture.