372 



during the active spraying season is necessary to reach a conclusive 

 understanding of the comparative vahie of spraying and fumigation. 

 An effort is being made towards closer co-operation between research 

 agencies and the citrus industry. 



Stirett (G. M.). Report of the Work on the Cabbage Maggot at 

 Burlington and Vicinity. — 16th Ann. Rept. Ontario Veg. Growers' 

 Assoc. 1920. Toronto. 1921, pp. 15-16. i Received' 21st May 

 1921.] 



Further experiments with mercury bichloride against the cabbage 

 maggot [Phorhia hrassicae] on radishes [R.A.E.. A., ix, 127, 128] 

 show that this is the most effective substance yet found for the control 

 of this pest. Two appHcations should be made, the first just after 

 the beginning of egg-laying and the second five days later. Used at 

 a strength of 1 oz. to 8 gals, of water slightly better results were 

 obtained than with 1 oz. to 10 gals. 



Caesar (L.). The European Corn Borer. — Ontario Dept. Agric. 

 42nd Ann. Kept. Agric. & Expt. Union. 1920, Toronto. 1921, 

 pp. 59-63. [Received 21st May 1921.] 



A brief account is given of the occurrence of the European corn- 

 borer [Pyrausta nubilalis, Hb.] in Ontario [R.A.E., A. ix. 147, 159, 

 160], the damage caused by it and general remedial measures to be 

 adopted. It is proposed to ask the Legislature for a special grant 

 in 1921 for the purpose of investigations with a view to discovering 

 some practicable method of controlling this pest. 



Fracker (S. B.). Division of Insect and Plant Disease Control. — 



Bienn. Rept. 1919-20. Wisconsin State Dept. Agric.. Madison, 

 Bull. 33, 31st December 1920, pp. 104-139, 19 figs. [Received 

 21st May 1921.] 



The potato leaf hopper [Einpoasca mali] was more numerous than 

 usual during 1919. Bordeaux mixture proved an efficient repellent 

 against it, and was used in many localities combined with Black Leaf 40. 

 The outbreaks of army worm [Cirphis unipnncta] during 1919 and 

 especialty 1920 proved the most severe since 1900. As the larvae 

 appeared just as the grain was ripening, it was possible to save the 

 crop by early harvesting. Grasshoppers were abundant in several 

 counties ; and owing to the difficulty in obtaining molasses, salt 

 was successfully used in some cases as the attractive principle in baits 

 for them. Special inspections have been organised to prevent the 

 spread of the gipsy moth [Porthetria dispar] from New Jersey, where 

 an extensive infestation was discovered in 1920 [R.A.E., A. ix, 351.] 

 Two small outbreaks of San Jose scale [Aspidiotus perniciosus] were 

 recorded ; the most heavily infested currant bushes were destro3'ed, 

 and other attacked fruit was thoroughly sprayed with dormant 

 strength lime-sulphur. 



Harley (H. K.). The European Corn Borer Survey. — Bienn. Rept. 

 1919-20, Wisconsin State Dept. Agric, Madison, Bull. 33, 

 31st December 1920, pp. 139-144, 3 figs. [Received 21st May 

 1921.] 



The life-history of the European corn-borer [Pyrausta nubilalis, 

 Hb.] as occurring in the vicinity of Boston is described, and the scouting 



