CHRYSANTHEMUM MIDGE. 



Table IV. — Length of complete life cycle. 



13 



Cage. 



Eggs deposited. 



Adult emerged.'- 



Leneth 

 of life 



cvele. 



Apr. 2. 



do. 



do. 



Anr. 29 to Ma v 2. 

 Apr. 30 to May 2. 

 May 1 to May 2. . 



Feb. 1... 

 Feb. 2... 

 Mar. 1... 

 Mar. 5 . . . 

 Mar. 6-9. 

 Aug. 3... 



do... 



Aug. 6. . . 

 Aug. 27.. 

 Aug. 29.. 



do... 



do... 



do... 



Sept. 21.. 



Mar. 4 



Mar. 4 to Mar. 7 



Apr. 8 to Apr. 22. . . 



Apr. 6 



Apr. 22 to Apr. 27.. 

 Sept. 4 to Sept. G... 

 Sept. 11 to Sept. 18. 



Sept.5 



Sept. 25 to Oct 4 . . . 

 Sept. 26 to Oct 3... 

 Sept. 27 to Oct 2... 



Oct 2 



Oct. 4 



Oct 24 to Xov 2 



Days. 

 27-30 

 28-30 

 29-30 



31 

 30-33 

 38-52 



32 

 47-49 

 32-34 

 39-46 



30 

 29-38 

 2S-35 

 29-34 



34 



36 

 33-42 



1 Data given in Table I show that mated females deposit eggs on date of emergence. 



In the spring of 1917, 1918 ; , and 1919, three distinct generations 

 were observed. The first generation started about the middle of 

 February and the last adults of this generation emerged during the 

 last few days of April. The second generation started about the 

 middle of March and the last adults issued around April 30. The 

 third generation started the latter part of April and emerged during 

 the early part of June. In the fall of 1918 when the occurrence 

 increased again a similar grouping of generations was evident, the 

 first beginning about the latter part of August, and the last adults 

 emerging during the first days of October. A second generation 

 started about the middle and latter part of September, maturing the 

 first days of November. The third generation was observed beginning 

 about the middle of October and the last adults emerged about 

 November 25. 



NATURAL ENEMIES. 



Felt (20), in speaking of the natural enemies of the midge, states 

 that — 



It was very likely brought to America without the normal quota of parasites and 

 for a time at least it may prove to be a somewhat difficult insect to control, though it 

 would seem as if the native parasites of our large and varied gall midge fauna might in 

 time prey most successfully upon this midge. 



Essig (18) mentions: 



During the summer a large number of parasites were reared from infested plants and 

 one species in particular did excellent work in the university greenhouse. The 

 material was sent away for determination and a few observations made as follows: 



Amblymerus sp. This hymenopterous parasite has been described by Mr. A. A. 

 Girault, through the kindness of Dr. L. 0. Howard, and a description is to appear 

 elsewhere. The adults are black with yellow markings on the legs. The females 

 vary from 1 mm. to 1.2 mm. in length, and the males are somewhat smaller. The 



