662 EXPERIMENT STATION RECORD. [Vol. 41 



tlvely by the Bureaus of Entomology and Plant Industry of the U. S. Depart- 

 ment of Agriculture. The results of the investigations are reported in part in 

 tabular form and summarized as follows: 



" Derris, known widely as a powerful East Indies fish poison, was found to ful- 

 fill several of the requirements of a general insecticide; it acts both as a contact 

 Insecticide and as a stomach poison, but is of no practical value as a fumigant. 

 Six species of derris were tested, but only two of them (D. illiptica and D. 

 uliginosa) were found to be satisfactory for insecticidal purposes. 



"According to the views of various authors, the toxic principle in derris is a 

 resin, which affects the various classes of animals according to the develop- 

 ment of their nervous systems. It liills some insects easily and others with 

 difficulty, but it usually acts slowly and seems to kill by motor paralysis. 

 Denatured alcohol was found to be a good economic solvent for extracting the 

 toxic principle, which when applied in spray mixtures proved to be efficient 

 against certain aphids, potato beetle larvae, and small fall webworms. For 

 proprietary insecticides It Is possible to incorporate the extracts from derris 

 into soft soaps, which when greatly diluted with water are ready for use. 



" Derris powder, used as a dust under practical conditions, was found to be 

 efficient against dog fleas, chicken lice, house flies, three species of aphids 

 (Aphis rumicis, A. pomi, and Myzus persicw), potato beetle larvae, and small 

 fall webworms, but of no practical value against bedbugs, roaches, chicken 

 mites, mealy bugs, Orthezia insignis, red spiders, or against the crawling young 

 of the oyster-shell scale. Used as powder in water with or without soap under 

 practical conditions, it proved to be efficient against most of the aphids sprayed 

 and also against cabbage worms {Autographa brassicce), the larvae of apple 

 da tanas (Datana ministra), oak worms {Anisota senatoria), small tent cater- 

 pillars, and potato beetle larvae." 



A list of 11 references to the literature Is Included. 



Economic poisons used in control of pests in California, season 1917—18, 

 G. P. Gray {Mo. Bui. Cal. Com. Hort., 8 {1919), No. 3, pp. 109-112, fig. 1).— 

 Data presented in tabular form show the cost of economic poisons by counties 

 and consumption, prices, and cost in 41 counties. 



Locust destruction {[Wellcome Trop. Research Lab.] Ent. Bui. 1 (1914), pp. 

 16). — Directions are given for the control of locusts by means of arsenlcals. 



The Coccobaclllus acridiorum of d'Herelle, D. S. S. Quiroga {Rev. Sac. Med. 

 Vet. [Buenos Aires], 4 {1918), No. 1, pp. 467-479). — This preliminary report to 

 the Agricultural Commission of Defense includes a list of 16 references to the 

 literature. 



Does Bordeaux mixture repel the potato leaf -hopper P 0. L. Fluke, jr. {Jour. 

 Econ. Ent., 12 {1919), No. S, pp. 256, 257).— The author presents data which in- 

 dicate that the leaf-hopper is repelled to some extent by Bordeaux mixture, 

 although further experimental work is necessary to prove such to be the case. 



The life history and biology of the pink and green aphid (Macrosiphum 

 solanifolii), L. B. Smith {Virginia Truck Sta. Bui. 27 {1919), pp. 27-79, figs. 

 12). — This is a detailed report of investigations commenced in the spring of 

 1915 at Norfolk, In which region M. solamfolii is a serious enemy of potatoes 

 and spinach, two crops of the greatest Importance In eastern Virginia, the 

 annual value of which Is about $12,000,000. 



In this paper the author deals particularly with certain phases of the life 

 history and habits of M. solanifolid as It occurs in the region of Norfolk, to- 

 gether with some of its economic relationships, the literature on which is re- 

 viewed. Including the studies of Patch (E. S. R., 34, p. 550), Houser et al. 

 (E. S. K., 38, p. 462), liegan (E. S. R., 38, p. 654), Britton (E. S. R., 39, p. 761), 



