222 EXPERIMENT STATION RECORD. 



Further experiments are in progress to determine the ultimate effect of con- 

 tinued weathering upon the constitution of the soil complex, and the relation 

 between alteration of the constitution of tlie bacterial flora and the ability of 

 the soil to deal successfully with burled green manures. 



On Actinomycetes in soils, I, F. MtJNTEB {CentN. Buki. [etc.], 2. AM., 36 

 {WIS), 'No. 15-18, pp. 365-381, pis. S, figs. 3).— The author gives an account of 

 investigations made on some soil-inhabiting fungi from widely separated locali- 

 ties in regard to their characters and life conditions. These studies include cul- 

 tures made in nutritive solutions and sand, as weU as on agar and gelatin, and 

 relate to their growth, their utilization of various sources of nitrogen and 

 carbon, and the influence of various degrees of acidity and alkalinity on their 

 growth. The results obtained are detailed in tabular form. 



The hypertrophied action of products elaborated by Rhizobium radicicola, 

 M. MoixiAKD {Compt. Rend. Acad. 8ci.. [Paris]. 155 {1912), No. 26, pp. 1531- 

 1534). — Cultures were made of R. radicicola from beans and the organisms 

 grown in suitable media for several days. The liquid was then filtered through 

 filter paper and porcelain to remove all organisms, and peas were grown with 

 tl\e aid of this filtrate. When so grown the roots showed hyperplasia in the 

 pericycle and a hypertrophy associated with a malformation of the cortical 

 cells. Where the hquid was first heated to 120° C. no such effect was noted, 

 indicating that the substance secreted by the micro-organism was destroyed 

 by heat. 



An efficient electrical incubator, H. J. Conn and H. A. Harding {New York 

 State Sta. Tech. Bui. 29, pp. 3-16, figs. 5.) — An apparatus for use in bacteriolog- 

 ical work is described which provides for incubation at both high and low tem- 

 peratures. It consists of 4 incubators of 7 cu. ft. capacity each, insulated with 

 cork board, heated by electricity, and one of them cooled by the drip from a 

 refrigerator. The incubators furnish temperatures between 19 and 50° C, while 

 in tlie refrigerator a temperature of from 7 to 10° is obtainable. 



The total cost of construction is estimated at less than $400, and the cost .of 

 maintenance at less than $40 per year. The advantages claimed for this type 

 of construction are high efficiency, low first-cost and maintenance cost, and 

 negligible fire risk. 



FIELD CROPS. 



[Field crops work at the Canadian experiment stations and farms in 1911], 

 J. H. Grisdale, C. E. Saunders, F. T. Shutt, J. A. Clark, R. A. Robertson, 

 G. A. Langelieb, W. C. McKillican, W. A. Munro, A. Mackay, R. E. Everest, 

 W. H. Fairfield, G. H. Hutton, and P. H. Moore {Canada Expt. Farms Rpts. 

 1912, pp. 5-9, 63-80, 116-137, W, U8, 155-157, 231-2^3, 251-260, 268, 269, 

 271-274, 283-296, 308-323, 3J,l-345, 3^9-354, 361-379, 389-401, 4II-4I6, pi. 1).— 

 This continues work already noted (E. S. R., 27, p. 334). 



The various farms conducted variety tests of spring and winter rye, spring 

 and winter wheat, oats, 2- and 6-rowed barley, emmer, spelt, peas, field beans, 

 maize for silage, sugar beets, turnips, carrots, flax, alfalfa, vetch, canary grass, 

 potatoes, broom corn, forage crops, and mixed grasses, the results being reported 

 in tabular form. 



The comparative values of various crop rotations at the central farm, consist- 

 ing essentially of meadow or pasture, roots or corn, and some cereal crop, hav6 

 been studied, special significance being given to their value as soil improvers 

 and their relative suitability for different lines of farming. The methods 

 employed in each of these rotations are described and tabulated results 

 are given. The net profits per acre from the various rotations ranged from 



