20 EXPERIMENT STATION RECORD. [Vol.41 



ammonia if the soil is made a suitable medium, and (c) the test as usually- 

 conducted fails to account for considerable amounts of ammonia which may 

 escape into the atmosphere or are converted into nitrate or nitrite. It is 

 stated, however, that the test can probably be employed by the soil chemist or 

 physicist to determine soil fitness. 



Ammonification of manure in soil, H. J. Conn and J. W. Bright {Jour. 

 Agr. Research [U. S.], 16 {1919), No. 12, pp. 313-350).— This contribution, from 

 the New York State Agricultural Experiment Station, supplements previously 

 reported investigations (E. S. R., 37, pp. 516, 517) and deals mainly with the 

 results of a detailed laboratory study of two of the most easily recognized types 

 of nonspore-forming organisms which are especially active as ammonifiers in 

 freshly manured soil, namely, Pseudomonas fluorescens and Bacillus caudatus, 

 renamed P. caudatus. The first part of the paper " shows the predominance 

 of these two organisms in manured soil and gives the results of an investiga- 

 tion of their function in soil. The second gives a detailed description of the 

 two organisms to aid in their identification by others." 



The results confirmed previous conclusions that the nonspore-forming bac- 

 teria are the most active ammonifiers in manured soil. " Pure cultures of 

 P. fluorescens and P. caudatus multiply much more rapidly in sterilized 

 manured soil than do pure cultures of B. cereus (selected as a typical spore 

 former). When sterilized manured soil is inoculated with a mixture of these 

 three organisms in pure culture, the two nonspore formers immediately gain 

 the ascendency, B. cereus occurring in too small numbers for detection by the 

 ordinary methods of study. 



" In field soil to which there has been no addition of organic matter for sev- 

 eral years, P. fluorescens and P. caudatus were rarely found, while B. cereus 

 was a common organism. When this same soil was mixed with manure and 

 potted, P. fluorescens and P. caudatus immediately multiplied rapidly, while 

 but small numbers of B. cereus spores and no active forms of B. cereus could be 

 found. 



"All three of these organisms are vigorous ammonifiers when tested in pure 

 culture. The activity of the nonspore formers and the absence of activity of 

 the spore formers in unsterilized manured soil leads to the conclusion that 

 P. fluorescens and P. caudatus are important ammonifiers of manure in soil, 

 while there is no evidence that B. cereus takes part in this process. 



" Detailed descriptions are given of the two ammonifying organisms studied. 

 The culture of P. fluorescens studied has been compared with other fluorescent 

 bacteria isolated from soil, and a review of the literature relating to fluorescent 

 bacteria has been made. It has not proved possible to fix definite limits for 

 this species. P. caudatus is the name now assigned to the organism previously 

 denoted by one of the writers as the ' orange-liquefying type.' It is apparently 

 identical with the organism described by Wright in 1895 and seems to be quite 

 common in soil and water." 



A list of 54 references to literature cited is given. 



Preservation of nitrog-en in liquid manure, Vogel {Zentbl. Agr. Chem., 47 

 {1918), No. 7, pp. 201-203; abs. in Chem. Abs., 13 {1919), No. S, p. 2//4).— It is 

 stated that sodium acid sulphate used at the rate of 40 kg. per cubic meter 

 (about 67.7 lbs. per cubic yard) is the best chemical agent for preventing loss 

 of nitrogen from liquid manure, material treated in this manner having given 

 excellent results in tests on meadow land and with rye, potatoes, and beets. 

 To avoid the caustic effects of the acid sulphate it is recommended that an 

 equal amount of gypsum be used in combination with it. The use of from 

 1 to 2 per cent of a solution containing formaldehyde and phenol resulting 



