ECONOMIC ZOOLOGY — ENTOMOLOGY. 363 



were similar to anesthesia, eliloroform should have been of greater value. If 

 the action were purely that of poisoning one would have expected the highly 

 poisonous hydrocyanic-acid gas to be of exceptional value for all species of 

 insects." 



Hydrocyanic-acid gas fumigation in California. — Fumigation of citrus 

 trees, R. S. Woglum (U. 8. Dept. Agr., Bur. Ent. Bui. 90, pt. 1, pp. rX+81, 

 pis. 8, figs. 12). — The author presents a succinct account of the completed re- 

 sults of fumigation investigations with a brief discussion of the salient features 

 of fumigation as ])racticed in California at the present time. " It is of the 

 nature of a handbook on the most up-to-date equipment, methods, and directions 

 in orchard fumigation. Full advantage has been taken of the results of other 

 investigators in fumigation; yet in such cases due credit is given to the proper 

 source. The information given in Bulletin 79 of this Bureau [E. S. R., 21, p. 

 354], which is a preliminary report on this investigation, has been largely 

 included in the present bulletin in summarized form." 



Hydrocyanic-acid gas fumigation in California. — The value of sodium 

 cyanid for fumigation purposes, K. S. Woglum (U. S. Dept. Agi:, Bur. Enl. 

 Bill. DO, pt. 2, pp. 83-f)0, pis. 2). — This paper records the results secured with 

 sodium cyanid during an investigation of the use of hydrocyanic-acid gas for 

 fumigation of citrus trees in California and is supplementary to the extended 

 report on the use of potassium cyanid above noted. A preliminary account by 

 the author has been previously noted (E. S. R., 23, p. 867). 



The author here discusses the jiroportion of chemicals to use. field tests, the 

 action of sodium chlorid, the kind of cyanid to purchase, dosages with sodium 

 cyanid including charts for field use, dosages recommended for scale pests, and 

 a com])arlson of sodium cyanid and iK)taKsium cyanid for general fumigation. 



" From the results of field work in this investigation it has been found that 

 the use of a high grade, or almost chemically pure, sodium cyanid produced 

 exactly as perfect a generation of gas in all cases as the use of a similar 

 grade of potassium cyanid ; in the majority of cases where used the generation 

 was apparently superior to that from a potassium cyanid." 



Preliminary report on the killing of rats and rat fleas by hydrocyanic- 

 acid gas, W. D. H. Stevenson (Sri. Mem. ]\lc(l. and Sanit. Depts. India, n. 

 scr., 1910, No. 38, pp. 28). — A general discussion of the subject, in which the 

 literature is reviewed, is followed by brief reports of 12 tests conducted. 



A fungicide and insecticide blower, E. Zacharewicz {Prog. Agr. rt. Vit. 

 (Ed. VEst-Centre), 82 (1911), No. IS, pp. 556-559, figs. 6).— The author figures 

 and describes an instrument to be used in applying powdered insecticides and 

 fungicides on a large scale to grain and field crops by means of horse power. 



Analysis of Paris green, 1910, J. W. Kellogg {Penn. Dept. Agr. Bui. 20Jf, 

 1911. pp. 33). — In 416 samples of Paris green analyzed, the arsenious oxid in 

 combination with copper was found to vary from 49.47 per cent to 57.6S per 

 cent, with an average of 55.10 per cent. Only 2 samples were found to contain 

 less than 50 per cent, the required amount of this form of arsenic. 



"The amount of water soluble arsenious oxid found present in the samples 

 analyzed varied from 0,72 per cent to 3.45 per cent, with an average of 1.32 

 per cent. None of the green examined was found to contain water-soluble 

 arsenic in excess of the amount restricted by law. The results obtained in 

 determining the total content of arsenious oxid showed the lowest percentage 

 to be 51.60, the highest percentage to be 61.2, with an average of 56.61 per 

 cent. The amount of copper, expressed as copper oxid, which was determined 

 in the samples received, was found to range from 26.75 per cent to 30.93 per 

 cent, with an average of 29.55 per cent." 



