120 " THE KEPOET OF THE No. 36 



Mrs. Thompson, Engiehart, various Pompons. Of these varieties Smith's 

 Advance, Ivory, Bonnafon, Wm. Turner, AVestcrn King, and Engiehart were 

 practically ruined. 



Felt' sta.tes that the insect has been recorded from central and southern Europe 

 as infesting Chrysanthemum leucantheinum, C. corymljo&um^ C. atratum, C. 

 japonicum and C. myconis. In America the pest was first noticed on the variety 

 known as Mistletoe. 



Nature of Injury. The gall (fig. 1, page 117) which is caused by the larva 

 irritating the pla,nt tissues occurs commonly on various portions of the chrysanthe*^ 

 mum plants. In the Ottawa greenhouse the galls were commonly found on the 

 leaves, stems and buds. The galls at one time were so abundant on some young 

 plants as to entirely deform them, as a result of which development was largely 

 stopped and no flowers borne. Many of the single-stemmed plants show con- 

 spicuous malformation of the stem resulting from early attack of the insect. In 

 the material received from the Victoria greenhouse the galls were found freely on 

 the stems and leaves. On some of the terminal leaves the presence of the insect in 

 conspicuous numbers had prevented growth and the leaves were clumped together 

 in more or less rosette fashion. 



Means of Control. 



In the Ottawa greenhouse some control work was conducted under the im- 

 mediate direction of Mr. J. McKee. Tlie greenhouse was fumigated during the 

 winter of 1915-16 with hydrocyanic acid gas about once every month. Such 

 fumigation destroyed the adults. The house was also fumigated with tobacco. 

 The cuttings from the stools were dipped before potting (in early December) in 

 nicotine solution in Xhe strength of % of an ounce to one gallon of water; the 

 plants were dipped a second time when repotted from 2%-inch pots to 4-ineh pots, 

 and a third time when transferred from 4-inch pots to 6-incli pots. During July 

 and August (1916) the chrysanthemums were sprayed with nicotine, in the same 

 strength, every three weeks. Since the first week of September to the present -^late 

 (October 16, 1916), the house has been fumiga'ted with tobacco once every ten days. 



AYhile the midge is still present in the greenhouse, it is by no means the pest 

 it was in 1915. The above treatment has undoubtedly kept the insect do^\^■l. 



In Mr. Woodward's greenhouse in Victoria, B.C., the following remedies ivere 

 tested : During the first week of treatment the ]>lants were fumigated with Black 

 Leaf 40 every night; in the following week they were fumigated three times, and 

 sprayed twice with Campbell's Nico Soap; during the third and fourth week the 

 plants were fumigated 'twice each week and sprayed once each week. Mr. Wood- 

 ward reported that as a result of this one month's treatment he had succeeded in 

 killing many adults, and thought he was slowly getting the insect under control. 

 The fumigation he reported was used as strong as the plants would stand Avithout 

 burning the foliage. 



The Eose Midge, Dasyneura rhndophaga Coq. 



In the report of the Dominion Entomologist for the year ending March 31st, 

 1915, a brief mention is made of the occurrence of this pest at London, Out.. 

 specimens of the infested shoots of the varietv Mrs. J. Laing having been received 

 at Ottawa in July, 1914. This was apparently the first record of the Rose Midge 

 in Canada. The grower reported that the buds on about 300 plants in his rose 



'31st Report of the State Entomologist, New York, 1915, p. 51. 



