365 



be destroyed. Another enemy is Tetrastichus sp. Many experiments 

 have been made with a view to controlhng the insect, and certain points 

 in the life-history bear upon these. The egg-stage may be controlled 

 by spraying or dipping the cuttings or plants [R.A.E., A, viii, 342]. 

 The adults can be controlled at the time of emergence by consistent 

 spraying and afterwards by fumigation. In cases of very shght 

 infestation daily picking of gall-infested leaves will hold the pest in 

 check ; when infestation is very heavy the most severely damaged 

 plants should be removed and burned. Fumigation should be done 

 every night for at least six weeks, in order to Idll all the adults that 

 emerge during this period and to prevent further oviposition. If 

 nicotine papers are used one sheet to 1,000 cubic feet of space will 

 8uflS.ce ; if hydrocyanic acid gas is employed | to ;^ oz. per 1,000 cubic 

 feet mil kill all adults. Fumigation must be started between 12.30 

 a.m. and 2 a.m., as the adults do not emerge until after midnight and 

 after 2 a.m. oviposition will have begun. If fumigation is impracticable, 

 spraying with 40 per cent, nicotine sulphate diluted to 1 : 800 with the 

 addition of |^ to 1 oz. per gallon of solution, should be practised every 

 afternoon for a period of 4 to 6 weeks. 



In Cahfornia the growing of the bulk of the chrysanthemum crop 

 under cloth is recommended as an efficient preventive against the 

 attacks of D. hjpogaea. Another method is to plant the stocks in 

 benches or cold frames directly after the season's crop has been re- 

 moved. This should be followed by thorough treatment with equal 

 parts of dry or air-slaked hme and tobacco dust. All new growth 

 should be kept covered with the mixture until further operations in 

 the spring. 



Baker (A. C.) & Moles (M. L.). U. S. Bur. Entom, A New Species 

 of Aleyrodidae found on Azalea (Hom.).— ^^^oc. Ent. Soc. 

 Washington, D.C., xxii, no. 5, May 1920, pp. 81-83, 1 plate. 



Aleurodes azaleae, sp. n., is described. This insect has been inter- 

 cepted by plant quarantine inspectors on shipments of azalea from 

 Belgium, Holland and Japan. It occurs frequently, but is not 

 abundant on the food-plant, only four or five pupa cases being found 

 to a leaf, and it does not seem, so far, to be injurious. 



Craighead (F. C). Direct Sunlight as a Factor in Forest Insect 

 Control. — Proc. Ent. Soc, Washington, B.C., xxii, no. 5, May 

 1920, pp. 81-83, 1 plate. 



Direct sunKght may be used as a highly eflScient method of 

 prevention or control of certain destructive tree-kilHng or wood- 

 boring insects. An assortment of infested mesquite sticks containiug 

 several species of Bostrychids in all stages, and larvae of Chnjsobothris 

 spp. and Cijllene antennatus, was placed in direct sunhght. In two 

 days 40 per cent, of all the insects to a depth of half an inch were killed ; 

 in a week 75 per cent, to a depth of three-quarters of an inch ; and in 

 two weeks 90 per cent, to the same depth. 



From June to September uninfested green mesquite sticks were laid 

 out in the sun and turned weekly for four to ten weeks. A few 

 Chrysohothris spp., and Bostrychids attacked the under-side of the 



