822 EXPERIMENT STATION RECORD. tVol. 43 



It Is claimed that in the lower halves of leaves suspended sidewise and 

 verticallj^ in moist air, the dry weight is greater than in the upper halves, this 

 fact indicating a greater movement of materials into the growing organs of 

 the lower half. In the water no such difference develops. 



Resistance of intracellular organisms to certain chemical substances, 

 V. Gai,ippe (Compt. Rend. Acad. Sci. [Paris], 169 {1919), No. 11, pp. 515-518).— 

 Notes are given of studies on intracellular microorganisms in both plant and 

 animal tissues. These organisms resisted ordinary disinfectants and remained 

 viable for a considerable time. 



The influence of some organic substances on the development of plants, 

 in, G. CiAMiciAN and C. Ravenna {Atti R. Accad. Ldncei, 5. ser., Rend. CI. Sci. 

 Fis., Mat. e Nat., 28 (1919), I, No. 1-2, pp. 13-20).— This work, a continuation of 

 that previously noted (E. S. R., 39, p. 526), deals principally with the develop- 

 ment of beech seedlings under conditions involving the addition of certain 

 organic substances to the nutritive medium. The authors' results and observa- 

 tions are given in some detail. 



A device for regulating the temperature of incubators either above or 

 below room temperature, J. H. Nobthkop (Jour. Gen. Physiol., 2 {1920), No. 4, 

 pp. 309-311, fig. 1). — The device described in this paper is said to have been in 

 use continually during several years and to have proved reliable and accurate. 

 It consists essentially in regulating the flow of water through the jacliet of a 

 double-walled incubator. The device is described, with explanation of adjust- 

 ments. 



FIELD CROPS. 



The unreliability of short-time experiments, F. S. Harris and N. I. Butt 

 {Jour. Amer. Soc. Agron., 12 {1920), No. 5, pp. 158-167). ^This paper, a contri- 

 bution from the Utah Experiment Station, reports studies of a number of irri- 

 gation, fertilizer, soil, and crop experiments at the station, the purpose of which 

 was to show the extent of fluctuations in yields during different years, the 

 influence of these fluctuations on results variously summarized, and the specific 

 dependence that should be given to data obtained in a given length of time. 

 Data are included from experiments using as crops potatoes, sugar beets, alfalfa, 

 corn, oats, and wheat. 



It was found that short-time experiments are especially subject to error 

 where a complete cycle of seasonal fluctuations is not includetl. All treatments 

 in an experiment are not affected relatively the same each season, the amount 

 of divergence varying in different years. Where variations from the average 

 conditions are large a greater number of years are required for accurate conclu- 

 sions than where the variations are small. Manuring experiments show wider 

 variations from the average than irrigation experiments. Under dry-farming 

 conditions variations are wider than under irrigation conditions, and small irri- 

 gations vaiy more than where the plant does not suffer for water. 



In these experiments potatoes varied the most in yield, followed in order 

 by sugar beets, alfalfa, com, oats, and wheat. Experiments requiring personal 

 judgment varied more than where measurements were mechanical. Average 

 results during several abnormal years ran contrary' to results in normal years 

 that followed. Progressive seasonal averages showed a gradual shifting of the 

 relative positions of part of the treatments in an irrigation experiment with 

 corn. In experiments where variations are comparatively large an exceptional 

 season may seriously affect the average of a 10-year period. 



[Report of field crops work at the Grand Rapids, Minn., Substation], 

 O. I. Bebgh (Minnesota Sta., Rpt. Grand Rapids Substa., 1915-1919, pp. 14-33, 



