ENTOMOLOGY. 969 



medi('ated simps and the mixtures thoroughly stirred. They were 

 I'eadily accepted by the bees. The bees were fed 4 days per week for 

 3 weeks and at the end of the period none of the ordinary symptoms 

 of foul l)rood had appeared. The medicated sirup was discontinued 

 for a week and then ordinary sirup containing spores was fed. Typical 

 symptoms of foul brood developed within 10 days, and within 1() days 

 the disease was well established. The author tried an experiment in 

 feeding- the filtrate from a "I weeks' old culture of B. alrei in saccharose 

 bouillon mixed in sirup, in order to determine whether any increased 

 resistance or immunity against foul })rood could be produced. After 

 3 weeks of this treatment, spores of the l)acillus were fed to the bees, 

 with the result that foul brood developed within 14 days. Brief notes 

 are given on the foul brood laws in force in the United States. 



The action of different rays of the solar spectrum on the devel- 

 opment of silkworms, C. Flammarion {Bui. Min. Agr. [France]^ 19 

 {1900}, j\'<K -J, pjK 860-86S). — The author experimented upon 720 silk- 

 worms, which were placed in 12 lioxes and subjected to different 

 colored lights. The silkworms were 6 days old when the experiment 

 began. The results of these experiments are tabulated in detail, and 

 the more important ones may be stated as follows: The maxiuuim pro- 

 duction of silk took place under plain, colorless glass; the next best 

 production of silk was obtained under clear, violet purple glass and the 

 smallest under a dark blue glass. A rather pronounced influence was 

 noted in different colored rays upon the determination of the sex of 

 silkworms. Under the colorless glass the number of females was 56 

 per 100, while under the blue glass it was 37 to 100. The author sug- 

 gests that this may be interpreted as meaning a variation in the nutrition 

 of the silkworms under the influence of dift'erent colored lights. 



Experiments in protecting man against mosquitoes by chemical 

 agents, C. E'ekmi and C. Lumbao {('enthl. Bali. u. Par., 1. AM., -28 

 {1900), No. 6-7, pp. 186-189). — Experiments were conducted for the 

 purpose of discovering substances which could safely lie used upon the 

 exposed parts of the body and which would kill mosquitoes. These 

 experiments, however, did not^deld promising results and were discon- 

 tinued. 



A number of experiments were tried in the destruction of mosquito 

 larvie in ponds of water. The substances used included lanolin, lard, 

 olive oil, castor oil, vaselin, petroleum, eucalyptus, verbena, tobacco, 

 onions, wormwood, acetic acid, carbolic acid, salicylic acid, and extracts 

 from animals which are resistant to mosquitoes. Besides the experi- 

 ments with simple substances, a number of other experiments were 

 tried wnth com l)i nations of two or more substances. Of the nearly 

 400 remedies which were thus tried, the following were the only ones 

 which gave satisfactory results: Castor oil, vaselin, allyl sulphid, and 

 benzine aldehyde, 2i per cent; water and eucalyptus, 2i per cent; 



