648 EXPERIMENT STATION RECORD. 



"(2) It is possible to grow these bacteria for at least thirty to thirty-five genera- 

 tions on special media without materially lessening their activity. 



"(3) Some cultures examined in the laboratory purporting to be cultures from the 

 alfalfa plant do not contain the germ from the alfalfa plant at all, but are cultures 

 of a soil organism resembling the germ from alfalfa in some particulars. 



"(4) The tubercle-forming bacteria of the legumes are easily destroyed by light, 

 consequently inoculated seed should be kept in the dark until used. 



"(5J Since some of the ordinary soil bacteria form colonies very similar to those of 

 the tubercle-forming bacteria and also resemble them to a certain extent in being 

 vacuolated, every culture, from which subcultures are to be made for distribution, 

 should be tested in pot experiments." 



Soil inoculation, L. L. Lewis, J. F. Nicholson, et al. (Oklahoma Sta. Bui. 68, 

 popular ed., pp. 9, fig. 1) . — This is a popular summary of the bulletin noted above. 



The quality of commercial cultures for legumes, H. A. Harding and M. J. 

 Prucha (New York State Sta. Bui. 270, pp. 345-385). — This bulletin gives the results 

 of bacteriological examinations in the laboratory of the New York State Station, and 

 in four other laboratories in different parts of the country, of 18 packages of the inoc- 

 ulating material for legumes formerly distributed in a dried condition upon cotton 

 by this Department and put on the market by commercial concerns. 



The examinations made it very evident that the packages were worthless for prac- 

 tical purposes, substantially identical results upon 6 of the packages being obtained 

 in the 5 separate laboratories. "It was shown that the failure of these cultures was 

 inherent in the method of their preparation rather than in any knavery of their pro- 

 ducers. While these results will explain the many failures from the use of cotton 

 cultures, they should not be understood as being opposed to the idea of treating the 

 seed of legumes with living bacteria." 



Commercial cultures for legumes not reliable, F. H. Hall, H. A. Harding, 

 and M. J. Prucha (Neir York State Sta. Bui. 270, popular ed., pp. 10, fig. 1). — A pop- 

 ular summary of the above bulletin. 



Soil bacteria, A. A. Brown (Jour. Dipt. Agr. Victoria, 3 (1905), No. 6, pp. 426- 

 437, figs. 3). — A general discussion of this subject, based largely upon Conn's treatises 

 (E. S. R., 13, p. 623; 15, p. 74). 



The micro-organisms of the soil, M. E. Kayser (Ann. Sci. Agron., 2. ser., 10 

 (1905), I, No. 3, pp. 432-449). — This is a review of investigations relating to nitrifi- 

 cation, denitrification, and fixation of nitrogen (symbiotic and nonsymbiotic). 



The nitrogen feeding of agricultural plants, Wein (Chem. Ztg., 29 (1905), No. 

 80, pp. 1066, 1067). — This is an abstract of a report before the section of agricultural 

 chemistry of the Society of German Naturalists and Physicians at the meeting at 

 Meran, September 24-30, 1905. 



The report discussed methods of conducting field experiments with fertilizers and 

 of interpreting the results. Summarizing the results obtained in comparative tests 

 of nitrate of soda, ammonium sulphate, and lime nitrogen on field, garden, and 

 forcing crops, the following conclusions are drawn: 



( 1 ) Lime nitrogen is as a rule not suited to top-dressing, but should be plowed in 

 to a moderate depth when applied. (2) With field crops lime nitrogen is only from 

 75 to 90 per cent as effective as nitrate of soda; with garden crops it is as effective 

 as nitrate of soda. (3) Sulphate of ammonia is as a rule as effective as nitrate of 

 soda except in case of small fruits, on which it is less effective than either nitrate of 

 soda or lime nitrogen. (4 ) This lower effectiveness is not believed to be due to evapo- 

 ration of ammonia, since lime nitrogen suffers a greater loss in this respect than 

 ammonium sulphate. The lower efficiency of the ammonium sulphate is believed 

 to be due to the injurious effect of the sulphuric acid of the salt. (5) The liberal 

 use of complete fertilizers affords a protection against frost and freezing, although 



