ECONOMIC ZOOLOGY ENTOMOLOGY. 245 



be of highest siguilieaucv to students of the action of insecticides iu the inter- 

 pretation of their experimental data." 



The author describes experiments conducted by E. E. Ong with a view to 

 determining the value of hydrocyanic acid gas as a soil fumigant. The method 

 devised consists in the use of a series of tubes in the soil, through which air 

 could be extracted and the amount of hydrocyanic acid gas quantitatively deter- 

 mined by the iodin test developed the previous year in the course of experi- 

 ments with scale-insect eggs. The results obtained were positive and definite. 

 Where the cyanid gas was pumped into the soil within a foot of the sampling 

 tube, only a very small fraction of 1 per cent was recovered. The soil evidently 

 filtered out the gas, either by absorbing or decomposing it. To determine the 

 capacity of the soil in terms of cyanid loss, calcium chlorid tubes were then 

 employed holding 50 cc. of soil, and gas of known strength pumped through, and 

 it was found that before any considerable quantity of cyanid could pass the soil 

 had taken nearly its full capacity, which was found to vary from 0.03 to 0.012 

 gm. per liter, or 122 to 440 lbs. of sodium cyanid per acre-foot. 



" While this amount makes the cost i^rohibitive for large use, it is well 

 within the possiblities for soil fumigation of small areas, and, indeed, is only 

 a little more expensive than carbon bisulphid in clayey soils, and much cheaper 

 In sandy soil and in any soil if the fertilizer value of the nitrogen in the 

 material is deducted. The dose will have to be regulated by the character of 

 the soil, since no results will be produced until after the soil has received the 

 full amount which it can absorb or decompose." 



New methods of studying the action of cyanid gas on scale-insect eggs are 

 Baid to have been employed with very satisfactory results, data having been 

 obtained on about 30.000 layings. The methods employed are briefly described. 



Report of the entomolog'ist, H. T. Fernald (Massachusetts Sta. Rpt. 1913, 

 pt. 1, pp. 55a-58a). — During the year the box leaf miner (Monarthropalpus 

 buxi), a recently imported insect, caused much injury to box trees and hedges. 

 It is pointed out that during the year over 90 per cent of the San Jose scales 

 examined were parasitized by a species, previously described by Tower as 

 ProspalteUa pernidosi (E. S. R., 29, p. 459). This parasite is said to have been 

 reported from Connecticut, New York, and Pennsylvania, and has been sent to 

 a number of other States for colonization. 



Insects injurious to stored raisins, F. T. Bioletti (California Sta. Rpt. 

 1914, PP- 189, 190). — It is stated that much injury is caused to raisins by in- 

 sects, the Indian meal or raisin moth (Plodia interpuncteUa) and the saw- 

 toothed grain beetle (Silvanus surinamensis) being the principal pests con- 

 cerned. Since the methods of control by screening and fumigation have proved 

 ineffective in many cases an investigation was undertaken, and it was found 

 that slight changes in the methods in use would insure protection. It is pointed 

 out that the fumigating rooms should be very carefully constructed to prevent 

 the escape of the gas, and should preferably be built of concrete. It is impor- 

 tant that improvements in screening and trapping devices be made and the 

 insects, usually allowed to escape when the raisins are passed through the siz- 

 ing and screening machines, be caught and destroyed. 



A study of the life history of the raisin moth indicates that their numbers 

 can be considerably reduced by carefully regulating the time of storage of the 

 raisins in the vineyard and packing house. 



The parasitism of insects by the Entomophthorese, F. Picard (Bui. 8oc. 

 Etudes et Vxilg. Zool. Agr., 13 (1914), Nos. 1, pp. 1-1; 2, pp. 25-30, pis. 2; 3, 

 pp. 37-40, pi. 1; 4, PP- 62-65). — This is a comprehensive review of the subject, 

 with references to the literature. 



