19171 ECONOMIC ZOOLOGY ENTOMOLOGY. 455 



to the abscised leaves than when applied to the leaves of potted plants. The 

 influence of Bordeaux mixture in increasing rates of water loss from abscised 

 leaves became apparent immediately after the spray dried upon the leaves. 

 The effectiveness of a film of Bordeaux mixture for inducing increased rates 

 of water loss appeared to vary considerably in different plants in the case of 

 abscised leaves and, to a lesser degree, in case of potted plants. 



Sulphur fungicides, G. P. Gray {Off. Rpt. Sess. Internat. Cong. Vit., 1915, 

 pp. IGO-lUf). — This is a discussion, largely from a chemical standpoint, of the 

 sources of the world's sulphur supply, the production, relative values, and 

 employment of forms more or less adapted to use as fungicides, the employment 

 of miscible sulphur and sulphur pastes, soluble homemade and commercial 

 sulphur preparations, and the compatibility of sulphur with other fungicides. 



ECONOMIC ZOOLOGY— ENTOMOLOGY. 



Laws relating to fur-bearing animals, 1916, D. E. Lantz (U. S. Dept. Agr., 

 Farmers' Bui. 7S3 {1916), pp. 28). — This is a summary of laws in the United 

 States and Canada relating to trapping, protection, propagation, and bounties. 



Canaries: Their care and management, A. Wetmore (U. S. Dept. Agr., Farm- 

 ers' Bui. 770 (1916), pp. 20, figs. 5).— This publication has been prepared to meet 

 requests received for information on the care of birds in sickness and in health. 



Shading effect of wire insect cages, H. H. Kimball (U. S. Mo. Weather 

 Rev., 44 (1916, No. 9, pp. 501-506, figs. 3). — Pyrheliometric measurements are 

 reported which " show that at normal incidence with the wire cloth the wires 

 intercept 0.332 of the solar radiation, or about what we would expect of 16-mesh 

 cloth made of No. 29 wire, American gage." 



Relationship between the wetting power and efficiency of nicotin-sulphate 

 and fish-oil-soap sprays, L. B. Smith (L*". S. Dept. Agr., Jour. Agr. Research, 



7 (1916), No. 9, pp. 389-399, figs. 2).— This is a report of investigations con- 

 ducted at the Virginia Truck Experiment Station on 27 one-twentieth acre 

 plats on which peas were sprayed five times and .spinach and strawberries once 

 with various mixtures of nicotin sulphate and fish-oil soap for the pea aphid, 

 spinach aphid, and red .spider, respectively. The wetting powers as well as the 

 nicotin content of the solutions were determined. 



The proportional efficiency of the sprays proved to be similar for each species. 

 " When more than 4 lbs. of soap were used with 10 oz. of nicotin sulphate to 

 50 gal. of water, there was a loss of both wetting power and efficiency. When 

 more than 8.75 oz. of nicotin sulphate were combined with 5 lbs. of fish-oil 

 soap to 50 gal., a loss occurred in both the wetting power and the efficiency. 

 When nicotin sulphate was used in quantities up to 10 oz. to a 1 : 50 fish-oil- 

 soap solution none of the resultant sprays had an efficiency of more than 75 

 per cent. Also, when fish-oil soap was used alone in quantities not exceeding 



8 lbs. to 50 gal., the highest efficiency ©f any of the formulas was only a frac- 

 tion over 75 per cent. It was found that the nicotin content of the solutions 

 remained the same irrespective of the amount of soap used. 



" The lo.ss of efficiency due to increasing the concentrations of the .solutions 

 is probably caused by a loss of both wetting pov/er and insecticidal value of 

 the soap. The loss of wetting power which occurs when the concentration of 

 the solutions is increased has a stronger tendency to reduce the efficiency of 

 the subsequent solutions if the original solution has an efficiency of 85 per cent 

 or more than it does if the original efficiency is below 75 per cent. 



"The actual importance of wetting power is difficult to determine in this 

 case, as the fish-oil soap has insecticidal propej-ties in itself. Where the wetting 

 82992°— 17 5 



