BOTANY. 645 



the absolute gain in dry matter and nitrogen content of the plants was in every ease 

 greatest where inoculation had taken place. In the experiments made with garden 

 soils the most important gains were invariably in those pots which had received 

 pure cultures of the nitrogen assimilating organisms. 



The influence of nutrition on the development of root tubercles on legumi- 

 nous plants, II. Fi.a.mani) ( IiKjhi. Agr. Gembloux, I / ( 1904), -V". /.:, pp. 755-765). 

 The author reports upon a series of experiments in which the effect of various sub- 

 stances on tin' development of tubercles on leguminous plants was noted. Seedlings 

 of peas, vetches, and beans were grown in water cultures, and at the end of the third 

 week the roots of the young plants were inoculated with a needle with portions of 

 fresh tubercles from beans or vetches. All the experiments were conducted in 

 duplicate, and the effect of various forms of nitrogen, potash, lime, and magnesium 

 on the development of the tubercles was noted. 



The formation of the tubercles seemed to be dependent on the nature and amount 

 of the salts present in the nutritive solution. No tubercles were produced where 

 potassium nitrate was present to a greater extent than 1 to 10,000 parts. The other 

 inorganic forms of nitrogen influenced the presence of root tubercles to a considerable 

 degree, and some of the organic forms, such as urea, oxamid, or potassium cyanid, 

 were very prejudicial to the production of root tubercles, even when used in very 

 dilute solutions. 



In the case of the vetches no tubercles were produced in the absence of magnesium, 

 and where neither lime nor magnesium was present there were no root tubercles on 

 either vetches or beans. The potash salts seemed to favor to some extent the devel- 

 opment of root tubercles, as did also lime salts. 



On the subsequent effect of soil inoculation of leguminous plants on 

 other cultivated plants, F. Nobbe and L. Richter (Landw. Vers. Stat., 59 {1908), 

 No. 3-4, pp. 175-177) . — The effect of inoculation of leguminous plants on subsequent 

 crops is shown by results obtained with oats grown after vetches, comparisons being 

 drawn between inoculated and uninoculated pots. The yield, dry weight, and 

 nitrogen content of oats were highest in every case where the previous crop had 

 been an inoculated one. 



Symbiosis in the genus liolium, E. M. Freeman {Minnesota Bot. Studies, 3. ser., 

 1904, pt. 3, pp. 329-334). — In a previous article (E. S. R., 14, p. 842) the author gave 

 a preliminary account of the symbiosis occurring in species of Lolium, in which the 

 intimate relationship between the fungus and the host plant was shown. The 

 existence of the fungus in Lolium temulentum, L. perenne, and L. italicum has been 

 demonstrated, but its life history has been determined only in the case of the first 

 species. It is believed that there is no material difference between the life-cycle of 

 the other species and that already known of the first mentioned. 



In ordinary commercial mixtures of seed of L. temulentum from 85 to 98 per cent 

 show the presence of the fungus hyphse in the hyaline layer, just exterior to the 

 aleurone cells. On germination the hyphse keep pace jn their growth with the 

 growing plant, and finally reach the young ovaries, developing luxuriantly. Since 

 the establishment of these facts the author has attempted in various ways, by alter- 

 ing the conditions of growth of the fungus, to induce it to form spores, but all efforts 

 have as yet failed. These failures are believed to be due to the habit of mycelial 

 infection having been so well established that the ability to form spores has been 

 lost, or the fungus may be some ergot-forming parasite, or one which forms spores 

 in some other organ of the host plant. 



Cultural investigations have been carried on which confirmed the results of pre- 

 vious anatomical research on the life history of the fungus. Plants affected and 

 without the fungus were placed under similar conditions. The entire crop of seed 

 was gathered, and from each lot 100 were examined, and in every case 100 per cent 



