BOTANY. 203 



outer tubes cause the water to tlow down on the side of the inlet and 

 up on the side of the outlet. 



The condenser may be inserted in the distillation tlask or in the 

 mouth of an extraction apparatus. 



Comparison of methods for the quantitative determination of starch in foods, 

 A. A. Loscii (InaiHj. Dins. St. relcrfihii7-{j, 1S90 ; ab.s. in Chem. Zt<j., 20 {1S9G), No. 54, 

 Eepert., p. ISl). — According to the brief al)stract, the Lest results were obtained when 

 twice as much normal sulphuric acid was used as called for iu the method of James 

 Biel. Where 3 times the amount of normal acid was used, the results were too low. 



Method for the determination of mustard oil in fodder cake, M. Passon 

 (Ztschr. angew. Cltcw., 1S96, No. 14, p. 422). — The method is clear, accurate, and 

 apparently simple, but requires the figure given in the text for its explanation. — 



C. L. PAKSONS. 



On the emulsifying properties of butter and oleomargarine, Schakfeu (Milch 

 Zig., 25 (1S90), No. 1, pp. 5-7). — A discussion of the emulsifying properties of butter 

 and oleomargarine and of the characteristic differences between the two. — f. w. 



WOLL. 



On the detection of adulterations in butter, F. Stohmann (Milch Ztg., 25 (1896), 

 pp.37, 38). — The author gives a summary of the data obtained for specitic gravity, 

 Hebner number, and Reichert-Meissl-Wollny number, by different chemists. Refer- 

 ences to the literature of the subject are included in the paper. — F. w. woll. 



Chemistry in daily life, Lassar-Cohn (Translated hy M. M. Pattison Muir. Lon 

 (Jon : H. Grtvel iS' Co., 1890, pp 324, Jigs. 21). — The book is a series of popular lectures. 

 The chemistry of combustion, respiration, niitrition of plants and animals, food, and 

 beverages are among the subjects treated. The chemistry of tanning, dyeing, soap 

 making, photographj', and other arts and industries is also treated of. 



BOTANY. 



Relation of gro-wth of leaves to the carbon dioxid of the air, 



D. T. MacDougal {Presented be/ore iSee. G of the America it Association 

 for the Advancement of Science, Aug., 1896; abs. in Science, n. ser., 4 {1S96), 



No. 91, PI). 435, 430). — A u umber of experiments Avere performed iu 

 which leaves were allowed to develop lu light and in darkuess under 

 conditions of functional inactivity. The amount of development 

 depended upon the availability of the stored food, the leaf depending 

 ordinarily upon its own activity for constructive purposes. Many 

 leaves died when inactive in the light due to an insufticient food supply, 

 and the disintegration of the chlorophyll was a result and not the 

 cause of death. 



On the resting periods of plants and the means of shortening 

 the same, J. Eriksson {Landmansbladc, 29 [189(J), pp. 20-25). — The 

 author discusses the problem of the resting periods of plants under 

 diflerent climatic conditions, and reports the results obtained by the 

 Danish plant physiologist, W. Johannesen, in his experiments investi- 

 gating the subject. The latter succeeded in shortening the resting 

 period of various plants by exposing the buds or bulbs for 24 hours to 

 an atmosphere saturated with chloroform or ether vapors. Very i)rom- 

 ising and interesting results were obtained in the work done so far; the 

 study of the subject is being continued by the author, — v, w. woll. 

 G128— Ko, 3 3 



