48 PROTECTION OF PLANTS — 1923-24 



entomologist-in-charge. During the previous year, Dr. Cameron in co- 

 operation with Dr. S. Hadwen, then pathologist of the federal Health of Ani- 

 mals Branch, incepted a joint study of the bot fliesaffecting horses , the results 

 of which were published in The Bulletin of Entomological Research, Vol. IX, 

 No. 2, 1918. In the same year. Dr. Cameron began studies of other blood- 

 sucking diptera, such as mosquitoes, tabanids and black flies. In 1918, too, 

 a remarkable outbreak of the Sugar-beet Webworm, Loxostege sticticalis Linn., 

 occurred in the Prairie provinces, particularly in Saskatchewan where millions 

 of migrating larvae caused widespread alarm. The outbreak of grasshoppers 

 {Camnula pellucida Scudd, and Melanoylus atlanis RilejO, in 1919, which 

 involved an area of approximately 1500 square miles, was investigated by 

 Dr. Cameron and Mr. M. P. Tullis, of the Provincial Department of Agri- 

 culture. This outbreak is discussed in Entomological Circular No 13. 

 In the following year the province was again subjected to a serious grass- 

 hopper infestation and, as I mentioned in my annual report for the two 

 years ending March, 1921, in regard to poisoned bait, "sawdust was employed 

 to a considerable extent. To the Entomological Branch belongs the credit 

 of first demonstrating under large acreage conditions the value of sawdust as 

 a cheap carrier for poison." In this year (1920), Mr. A. Kelsall (Insecticide 

 Investigations) spent the greater part of the months of June and July in the 

 neighborhood of Carlyle, Sask., in order to investigate further the value of 

 various poisons for killing grasshoppers and dust mixtures, contact sprays, 

 poison gas and poisoned baits were experimented with. A brief account of this 

 work is given in the report referred to above. Officers of the Branch have 

 kept in close touch with provincial offi.cers during the whole of the recent 

 grasshopper campaign. 



Dr. Cameron's permanent appointment with the Branch terminated in 

 October, 1920, but in the summer of 1921, pending the appointment of a 

 successor, he was re-employed at Saskatoon. Mr. K. M. King was appointed 

 in August, 1922, as entomologist in charge of the laboratory. Since his 

 appointment he has been specially interested in soil-infesting insects, parti- 

 cularly cutworms and wireworms. In 1923, he incepted a series of soil faunal 

 studies in co-operation with the Departments of Field Husbandry and Physics 

 of the University of Saskatchewan. In the same year, an outbreak of the 

 North- West Chinch Bug, Blissus occiduus Barber, closely allied to the true 

 Chinch Bug, was investigated by Mr. King in the vicinity of Lacadena. 



Previous to the establishment of a permanent laboratory at Saskatoon, 

 Mr. Norman Criddle, in charge of the Treesbank, Man., laboratory, assisted 

 materially in entomological investigations in the province. In 1915, he 

 studied the outbreak of the lled-backed Cutworm, Euxoa ochrogaster On., 

 wliich infested territory extending from Selkirk in Manitoba to Fort Pitte 

 and Lloydminster on the western boundary of Saskatchewan. In the vicinity 

 of Wadena, Sask., it was estimated that 3,000 acres of crop were damaged, 

 of which 1750 acres were totally destroyed. In 1916, Mr. Criddle noted the 

 spread of the Western Wheat-stem Sawfly^ into that portion of Saskatchewan 

 adjoining the south western region of Manitoba. 



The Division of Forest Insects have investigated outbreaks of torest 

 insects particularly in Northern Saskatchewan. In 1922, Dr. Swaine visited 

 the spruce areas along the lower Saskatchewan river and on the Porcupine 

 Forest Reserve. Extensive outbreaks of the Destructive Spruce Bark-beetle, 

 Dendroctonus -piceajjerda Hopk., were investigated and the Larch Sawfly was 

 noted to be increasing in the areas visited. In 1923, Mr. Norman Criddle, 



