ECONOMIC ZOOLOGY ENTOMOLOGY. 349 



after a meal, for 9 months. Unfed at a temperature of 75" with humidity be- 

 tween 65 and 70 an average life of 10 days, and an individual survival of up 

 to 21 days, is possible. At 88°, with humidity between 70 to SO, the average 

 life is shortened to 7 days, the longest survival being 11 days. At 96° with 

 humidity at 25 the average life is reduced to 5 days; individuals have survived 

 for 8 days. Exposure to 113° is fatal within a few minutes." 



White fly control, 1914, J. R. Watson {Florida Sta. Bui. 123 (WW, pp. 

 3-23, figs. 5). — This bulletin reports upon the white fly work carried on at the 

 station in 1914 in continuation of that previously noted (E. S. R., 31, p. 751). 

 A summarized account of the citrus white flies and means for their control is 

 included. 



The drought caused the 1914 fall brood of white flies to be the largest that 

 Florida has had for several years. It was found that the red and brown fungi 

 can be dried and kept over winter. It is pointed out that the ideal method of 

 controlling the white fly is to spread parasitic fungi during the rainy season 

 and to spray with miscible oil emulsion in spring and fall ; that the planting of 

 chinaberry and umbrella trees in citrus communities should be prohibited by 

 law ; and that owners of noninfested groves should adopt quarantine measures. 



A list of important papers on citrus white fly is appended. 



Injury to tropical trees by Pseudococcus filamentosus, P. Vayssi^re {Jour. 

 Agr. Trop., 14 {19U), No. 154, PP- 109-111; ahs. in Internat. Inst. Agr. [Rome], 

 Mo. Bui. Agr. Intel, and Plant Diseases, 5 (Wl-i), No. 7, pp. 969, 970).— This 

 mealy bug, described in 1893 from Hawaii, has since been found in various 

 parts of the world. The branches and leaves of infested trees are covered by 

 masses of white filamentous waxy matter, which sometimes forms sheets join- 

 ing one branch to another. Severely attacked trees may be killed in a few 

 months. 



Petroleum emulsion (6 to 15 per cent) applied as a winter wash appears 

 to be the best insecticide for use in its control. Cryptolcemus montrouzieri has 

 been found to be very efficient against this scale in Hawaii. 



The relation of variation in the number of larval stages to sex develop- 

 ment in the gipsy moth, F. H. Moshkk and R. T. Webbee {Jour. Econ. Ent., 

 7 (1914), No. 5, pp. 368-^73).— Observations which indicated that the larvae 

 that pupate in the fifth stage produce male moths and those pupating in the 

 sixth stage produce female moths led the authors to conduct experiments which 

 have shown that the variation is quite constant. Of 560 larvte which trans- 

 formed Into chrysalids 325 pupated in the fifth stage and produced males, while 

 the remaining 235 passed into the sixth stage and developed female pupae. On 

 several occasions the scarcity of certain foods necessitated the stinting of 

 caterpillars but regardless of this fact the females passed through the addi- 

 tional larval stage. The authors have never found a seventh molt as reported 

 by some observers. 



" There can be no doubt but that the gipsy moth is changing or has changed 

 its habits in this country. . . . That the insect itself is less hardy than in 

 the past is a surety and it is far more susceptible to disease." 



Contributions to the life history of the lesser peach borer in Ohio, J. L. 

 King {Jour. Econ. Ent., 7 {1914). No. 5, pp. 401-403).— A report of observations, 

 made in the lake regions of northern Ohio during the summer of 1913, which 

 show that Synanthedon pictipcs has one full brood and a partial second brood 

 in the Lake Erie district. The second brood larvae emerge as adults during 

 August and the first week in September. 



Cutworms, H. T. Fernald (Massachusetts Sta. Circ. 43 (1914), pp. 2). — A 

 revision of Circular 2, previously noted (E. S. R., 19, p. 758). 



