ECONOMIC ZOOLOGY ENTOMOLOGY. 255 



of molting. Immediately after molting the effect of the poison is manifested 

 most strikingly. ^ 



The author believes that in comparing the different effects of poisons, observa- 

 tions should be made on the third day after the poisons are applied and that 

 the average and maximum mortality can be determined more certainly on the 

 .seventh or eighth day. Barium chlorid is a very effective insecticide, but nuist 

 be used at a strength 8 to 12 times as great as arsenicals In order to produce 

 the desired results. It dissolves readily in water, however, and is inoffensive 

 for man. Arsenate of lead appeared not to be as active as Paris green, but 

 caused a rapid paralysis in the insects which ate it. 



The zoological bulletin of the division of zoology, II. A. Surface (Zool. 

 fiul. Pom. Drpt. Agr., 5 (1907), No. 2, pp. 32-6 Ji, pU. 2).— Brief mention is 

 made of various practical methods for the application of sprays and of other 

 insecticide methods. A spray calendar is also included in the bidletin. 



Early spring applications of insecticides for the oyster-shell scale. The 

 occurrence and distribution of San Jose scale in Vermont, W. Stuart (Ver- 

 mant ma. Rpt. 1906, pp. 293-291, pi. i).— Oyster-shell scale is widely distributed 

 in the orchards of Vermont. Infested trees were sprayed in March with lime- 

 sulphur-salt mixture, prepared according to the formula 25 :16.5 :16.5 :50. The 

 mixture was boiled with steam. This insecticide gave better results than any 

 of three proprietary remedies compared with it, but not all of the scales were 

 killed. Spring treatment is not recommended for this insect. 



San Jose scale has been known to be in Vermont for the past 8 years. Atten- 

 tion is called to the danger of infestation with this insect. Lime-sulphur wash 

 is recommended for eradicating it. 



Lime-sulphur washes for the San Jose scale, A. L. Quaintance (U. S. Dept. 

 Agr. Yearbook 1906, pp. ^29-'/46. pis. 3, flgs. 2). — Lime-sulphur wash was first 

 used for San Jose scale in California, and its use has gradually spread over the 

 country. A historical statement is given of the early experiments with this 

 insecticide, together with notes on the importance of the different elements in 

 the wash, the variation in the formulas which have been proposed and the chem- 

 ical changes taking place in the preparation of the wash. Recommendations 

 are also made regarding the time of application, the necessary equipment for 

 spraying, and the range of usefulness of the lime-sulphur prepai'ations. 



Bacteriological studies on foul brood and sour brood of bees, R. Burri 

 ( Bakteriologischc Untersiichiuigcit iibcr die FaulhnU unci Sauerbrut dcr Bieiien. 

 Aarau: H. R. Sauerldndcr cf- Co., 1906, pp. IV+40, pi. 1, fig. 1).—A series of 

 bacteriological studies was carried out for the purpose of determining the bac- 

 terial cause of foul brood and sour brood. 



It is found that in Switzerland foul brood may be caused by infection with 

 Baeillus alvel and also by another bacillus which appears to be a new species 

 and is difficult to cultivate. The two organisms may be distinguished by the 

 fact that in dead larvse B. alvei is found in the form of rods and spores and 

 Ijroduces a strong odor, while the other bacillus causes no odor and is found 

 only in the form of small spores. Other species of bacilli were found not to 

 be connected with foul brood. 



Larvae affected with sour brood are characterized by an acid odor, dirty yel- 

 low color, and inc-reased hardness of the chitin coat. In affected larv;e large 

 numbers of bacteria resembling luctic-acid bacilli are found. Both foul brood 

 and sour brood may occur simultaneously in the same hive, but the author 

 believes that foul brood is usually caused by the new species of bacillus which 

 he lias discovered. 



Report on a disease of bees in the Isle of Wight, A. D. Imms (Jour. Bd. 

 Agr. [London], U {1901), No. 3, pp. 129-lJfO, figs. 3).— The bee keepers of the 

 14639— No, 3—07 5 



