454 EXPEKIMENT STATION KECORD. 



during this period, and no surrounding breeding host for the species. The 

 spraying should, as a rule, be continued up to 3 or 4 weelvs of harvest time. In 

 spraying for thrips the nozzles should be held well down upon the plants and 

 the spray applied with as much force as possible." 



Where sets are used considerable injury may be prevented by dipping them 

 about a week before planting in nicotin sulphate at about the same strength 

 as used for spraying and then giving 2 dippings in the same insecticide at 

 planting time, or in almost any other of the solutions mentioned, including 

 kerosene emulsion. Since this thrips displays preference toward cabbage' and 

 cauliflower, neither of these two crops should be grown contiguous to onions. 



Brief accounts are given of several species of root maggots, including the 

 seed-corn maggot (Pegoniya fusciceps) ; the imported onion maggot (P. cepe- 

 torum) ; the black onion fly (Tritoxa flcxa) ; the barred-winged onion fly 

 (Chatopsis oenea) ; and of remedial measures therefor. While the imported 

 onion maggot is very destructive to nearly all forms of the onion family, there 

 are quite as many, if not more, records of the seed-corn maggot doing the more 

 abundant injury to onions, as well as to root crops in general and to many seeds. 

 The seed-corn maggot, which first came into prominence in about 1902 although 

 known here for many years before, is said to be greatly on the increase. Cut- 

 worms and wireworms are also briefly discussed. 



Some important insect enemies of live stock in the United States, F. C. 

 BiSHOPP (U. S. Dept. Agr. Yearbook 1912, pp. 383-396, pis. 2, figs. /,).— This 

 brief popular account deals with the buffalo gnat (Simulium pecuarum), the 

 turkey gnat (S. meridional e) , horseflies, gadflies, earflies, botflies, the horn 

 fly {Lyperosia irritans), the stable fly (Stomoxys calcitrans), the screw worm 

 {Chrysomyia macellaria) , the bedbug (Cimex lectularius) , Mexican chicken 

 bug {Hwma to siphon inodora), sucking lice, and biting lice. 



A new fruit and truck crop pest (Irbisia brachycerus), E. J. Vosleb {Mo. 

 Bui. Com. Hort. Cal., 2 (1913), No. 6, pp. 551-553, figs. 3).— A capsid, recently 

 redescribed as Capsus solani, has been seriously damaging peaches ii^ Solano 

 County, Cal., by puncturing the skin and causing the sap to ooze out, and has 

 also attacked radishes, rhubarb, roses, etc. 



The aphids on mangolds and allied plants, F. V. Theobald (Jour. Bd. Agr. 

 [London^, 19 (1913), No. 11, pp. 91J,~922. pi. 1, figs. 3).— This continuation 

 of the paper previously noted (B. S. R., 28, p. 252) deals with the boat gall 

 or green mangold aphis (Aphis atriplicis) and several species of lesser im- 

 portance, namely, the allied green mangold aphis (Rhopalosiphum bctw n, sp.), 

 the short-siphoned mangold aphis (A. brevisiphona n. sp.), and the teasel aphis 

 (A. ochropus). A brief discussion of preventive and remedial measures for 

 the mangold, bean, and beet aphis is appended. 



The walnut mealy bug' (Pseudococcus bakeri), R. S. Vaile (Mo. Bui. Com. 

 Hort. Cal., 2 (1913), No. 6, p. 55.'^). — This paper is supplementary to that by 

 Essig previously noted (E. S. R., 25, p. 53). 



"The known host plant list at present is as follows: Walnut, apple, pear, 

 orange, lemon, pomelo, elder, cottonwood, southern California black walnut, 

 nightshade, and a few of the ornamental shrubs. It has been found in 3 localities 

 in Ventura County infesting citrus trees, but in 2 of these cases it occurs in 

 much greater numbers on the native elder and nightshade surrounding the 

 trees. For at least a portion of the year it lives primarily on the roots of these 

 2 plants. Numerous Solanum bushes growing under orange trees have been 

 found with the roots thickly covered with all stages, from eggs to mature 

 adults. The same has been true of the elder, though so far no specimens 

 have been reported on roots of citrus or other fruit trees." 



The life history appears to be much the same as that' of P. citri. 



