456 EXPERIMENT STATION RECORD. [Vol. 41 



Preliminary memorandum on current views as to the damage done to 

 stored grain and flour by insects and mites, and the best means of preven- 

 tion (Roy. Soc. [Londoni, War Committee Memo. 1 (1918), pp. 2). — A brief 

 reference to the Uterature. 



Some necessary steps in any attempt to prove insect transmission or 

 causation of disease, W, D. Pierce (Hclencc, n. ser., 50 (1919), No. 128^, pp. 

 125-130). — An outline of the steps necessary for successful investigation. 



Clean cultivation in its relation to the control of insect pests, H. H. King 

 (IWcUcome Trop. Research Lab.] Ent. Bill. 8 {.1918), pp. .'/). — A brief discussion. 



A comparison of the toxic action of volatile substances on insects, G. Beet- 

 band and Mks. M. Rosenblatt (Compt. Rend. Acad. Sci. [Paris], 168 (1919), 

 No. 18, pp. 911-913). — Of the eight substances tested by the authors on the 

 caterpillar of Bomhyx neiistria chloropicrin was found to be most toxic, being 

 slightly more so than hydrocyanic acid gas. 



The Pentatomoidea of Illinois, with keys to the Nearctic genera, C. A. 

 Hakt (III. Dept. Reyiatr. and Ed., Div. Nat. Hist. Survey Bill, 13 (1919), Art. 

 7, pp. 157-223, pis. 6). — This work, edited by J. R. Malloch, the manuscript hav- 

 ing been only partly completed at the time of the author's death, includes de- 

 scriptions of nine species and a genus (Cydnoides) new to science. 



The fungus parasite of the periodical cicada, A. T. Speaee (Science, n. ser., 

 50 (1919), No. 1283, pp. 116, ii7).— This is a preUminary account of studies of 

 Massospora cicadina, a detailed report of which is soon to be issued. 



The beet leaf hopper. — A report on investigations into its occurrence in 

 California, H. H. P. Sevekin (Facts About Sugar, 8 (1919), Nos. 7, pp. 130, 131, 

 13 J,, fig. 1; 8, pp. 150, 151, fig. 1; 9, pp. 170, 171, 173, fig. 1; 10, pp. 190, 191, fig. 

 1; 11, pp. 210, 211; 12, pp. 230, 231, fig. 1; 13, pp. 250, 255, fig. i).— This report 

 is accompanied by tables which give the details relating to the occurrence of 

 the beat leaf hopper in California. The data thus presented include the number 

 of beet leaf hoppers captured on plants in the desert and in the cultivated 

 area of the Imperial Valley, on the plains and foothills, and in the cultivated 

 area of the San Joaquin Valley, and under natural conditions and in the culti- 

 vated area of Salinas Valley; lists of plants in which the beet leaf hopper 

 deposited eggs in the cultivated ai'ea of the San Joaquin, Sacramento, and 

 Salinas Valleys; plants on vrhich the beet leaf hopper was collected and trans- 

 mitted curly leaf to sugar beets; plants from which the beet leaf hopper was 

 reared and transmitted curly leaf to sugar beets; number of dark male and 

 female beet leaf hoppers captured in cultivated and natural breeding areas; 

 and number of days beet leaf hoppers lived without food during winter. 



A review of the leaf hoppers of the genus Gypona north of Mexico, E. H. 

 Gibson (Proc. U. S. Nat. Mus., 56 (1919), pp. S7-i6>0).— Thirty-three species are 

 recognized, of which eight are described as new to science. 



Report to the froghopper committee on Mr. Glasgow's supposed cure for 

 froghoppers, C. B. Williams (Bui. Dept. Ayr. Trinidad and Tobago, 18 (1919), 

 No. 1, pp. 10-15, figs. 4)- — Demonstrations given failed to prove the liquid suffi- 

 ciently effective in destroying either the eggs or nymphs of the froghopper or 

 the fungi causing root disease. 



A species list of the Aphididse of the world and their recorded food plants, 

 H. F, Wilson and R. A. Vickery (Trans. Wis. Acad. Sci., Arts, and Letters, 19 

 (1918), pt. 1, pp. 22-355).— The first part (pp. 26-180) of this Ust consists of a 

 .•species list of the Aphididas of the world with their recorded food plants, and 

 the second part (pp. 181-355) of a list of aphid food plants and the aphids said 

 to attack them. 



