1917] AQBICULTUEAL BOTANY. 429 



[Commercial fertilizer analyses] iOfj. Bui. Bd. Agr. Ohio, 8 (1917), No. 1, 

 pp. 65-fi2). — This section of the refxirt contains the results of actual analyses 

 of 76 samples of mixed fertilizers, 5 samples of bones, and 4 samples of unmixed 

 fertilizing materials collected for inspection In Ohio during 1916, together with 

 a list of brands of fertilizers licen.sed from January 1 to February 1, 1917. 



Fertilizer registrations for 1917, C. S. Cathcabt {New Jerney Stag. Bui. 

 304 (1917), pp. .5-.}2;. — This bulletin contains the List of fertilizer registrations 

 received in New Jersey for 1917 up to January 22. 



AGEICULTTJEAL BOTANY. 



Periodicity in transpiration, Sophie J. Wilkie (Tram, and Proc. Dot. Soc. 

 Edinb., 21 (1915-16), pt. 1, pp. 59-64, fiffS- 2).— The author has employed the 

 apparatus previously described (E. S. R., 34, p. 729) In tests with Pinus syl- 

 vestru, Opuntia occidentalis, and Lilium rubrum as herein detailed. She has 

 found that under ordinary conditions there is a daily periodicity in tran-spira- 

 tion by the.se plants, which show also individual differences in this respect, 

 transpiration being active but erratic In darlines.s. 



Comparison of the hourly evaporation rate of atmometers and free water 

 surfaces with the transpiration rate of Medicago sativa, L. J. Bbigcs and 

 H. L. SHA>fTz {V. S. Dept. Agr., Jour. Agr. Research, 9 {1917), No. 9, pp. 277- 

 292, pis. 3, figs. 4). — The authors report a study of the individuality of evapor- 

 ating .surfaces as related to the hourly tran.spiration rate, employing M. sativa 

 and the four types of porou.s-cup atmometers designed and u.sed by Livingston 

 (E. S. R., 33. p. 320; 34, pp. 34, 521), evaporation tank.s which are described, and 

 a filter-paper evaporimeter of special design. The measurements were made 

 at Akron, Colo., during a period of hot, dry weather in July, 1916. 



The various atmometers, though differing widely in form, gave graph.s which 

 are similar in their characteristics. No very close corre.spondence was ob.served 

 between the hourly tran.spi ration rate of alfalfa and the hourly evaporation rate, 

 as given, of any of the .systems employed. The departure of the hourly evapora- 

 tion rate of the porous-cup atmometer from the hourly transpiration rate of 

 alfalfa is considered to be due largely to the Increase in evaporation over trans- 

 piration during the night, to the sensitivity of the atmometers to changes of 

 wind velocity (not accompanied by like changes in transpiration), and to de- 

 ficient resi»onse by the atmometers to changes in solar radiation. 



Lack of high correlation between evaporation and the hourly transpiration 

 rate does not neces-sarily involve low correlation on a daily basis. 



The plant may not respond freely to its environment but that fact is not con- 

 sidered proved by a departure of relative transpiration rate from evaporation 

 rate in an arbitrarily chosen physical system. 



The relationship existing between the oxidase activity of plant juices and 

 their hydrogen ion concentrations, with a note on the cause of oxidase ac- 

 tivity in plant tissues, H. H. Bc:^zel {Jour. Biol. C'hem., 28 {1916), No. J, 

 pp. S15-333. figs. 3). — In continuation of a general body of work begun some 

 years ago, reports on which have been noted as given by the author (E. S. R., 

 27, p. 9; 29. p. 48; 31, p. 748) or by True and Stockberger (E. S. R., 36, p. 

 127), the author undertook to study the oxida.se activities of various plant 

 tlssups in different hydrogen ion concentrations, hoping that such study might 

 throw some Light on the nature of the acid effect and furnish further data on 

 the comparative behavior of oxidases from different sources. An account is 

 given of the methods employed. The results as tabulated are considered to 

 corroborate in a quantitative way the findings of other exi)erimenters cited 



