8 BULLETIN 778, U. S. DEPARTMENT OF AGRICULTURE. 
during the latter part of October or the first three weeks of Novem- 
ber, at which season the last generation of larve leaves the plants, 
enters the ground, and constructs overwintering cocoons. If depend- 
ance is placed on the dust alone, it is imperative that the application 
be so timed as to be on the soil before the larvee seek winter quarters. 
No hard and fast rule governing the date of this application can be 
recommended for all localities, since temperature naturally influences 
the final disappearance of the larve. 
PRECAUTIONARY MEASURES. 
The rose midge can be kept out of greenhouses if proper precautions 
are exercised. Under no condition should infested plants be taken 
into a house free from this pest. Plants should not be purchased 
knowingly from firms which carry infested stock, and should be 
bought with the understanding that they are free from the midge 
either in the buds or in the soil. Before new. stock is placed in a 
house, all plants should be examined carefully, and suspicious ones 
destroyed or returned to the shipper. 
LITERATURE CITED. 
(1) UNITED STATES DEPARTMENT OF AGRICULTURE, DIVISION OF ENTOMOLOGY. 
1888-89. In. Insect Life, v. 1, p. 284. 
(2) WEBSTER, I. M. 
1904. Studies of the habits and development of Neocerata rhodophaga 
Coquillett. J Bulletin of the Illinois State Laboratory of Natural 
History, v. 7, art. 2, p. 15, p. 21-23. 
(3) Davis, J. J. 
1912. Report on insects injurious to flowering and ornamental green- 
house plants in Dllinois. In Forbes, 8S. A., Twenty-seventh Report 
of the State Entomologist on the Noxious and Beneficial Insects 
of the State of Illinois, p. 109. 
(4) FE xT, E. P. ; 
1915. Twenty-ninth Report of the State Entomologist on Injurious 
and Other Insects of the State of New York, p. 131. (University 
of the State of New York Museum bulletin 175.) 
(5) Hewitt, C. GORDON. 
1915. Report of the Dominion Entomologist for the Year Ending 
March 31, 1915, p. 33. 
(6) Tur AMERICAN ROSE ANNUAL. 
1916. Page 68. 
(7) SwoperaAss, R. E. 
1917. Some of the important insect pests of Indiana. Jn State En- 
tomologist of Indiana, Ninth Annual Report, 1915-16, p. 146. 
(8) Gipson, ARTHUR. 
1917. Three important greenhouse pests recently introduced into 
Canada. Jn Entomological Society of Ontario, Forty-seventh An- 
nual Report, 1916, p. 120-121. 
O 
