UNITED STATES DEPARTMENT OF AGRICULTURE 
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1 BULLETIN No. 643 
Contribution from the Bureau of Entomology 
L. O. HOWARD, Chief 
S&?*%J-L. 
Washington, D. C. 
March 8, 1918 
THE MELON FLY. 1 
By E. A. Back, Entomologist, a-nd C. E. Pembekton, Assistant Entomologist, 
Mediterranean and Other Fruit Fly Investigations. 
CONTENTS. 
What the melon fly is like 3 
Origin and distribution 4 
Establishment and spread in Hawaii 4 
Methods of spread 7 
Economic importance 7 
Nature of injury caused by the melon fly 8 
Food or host plants 16 
Page. 
Interesting facts concerning the adult fly 22 
Why the melon fly is a serious pest 24 
Control measures 25 
Measures taken to keep fruit flies of Hawaii 
from gaining a foothold in continental 
United States. 
Summary . 
THE MELON FLY is a serious pest that never should have 
gained access to the Hawaiian Islands. Its establishment in 
Hawaii came naturally enough, as in the case of many of our worst 
insect enemies, along with the development of unrestricted modern 
commerce, and owing to the lack, in earlier days, of a knowledge of 
pests in other lands likely to be introduced into ours, or of any 
quickened public opinion which, at last thoroughly alive to the 
great financial losses that may be averted, is to-day heartily sup- 
porting Federal quarantines directed against just such pests as 
the melon fly. 
The melon fly is now established thoroughly throughout the 
coastal regions of the Hawaiian Islands and never will be eradi- 
cated. It attacks many vegetables that otherwise could be grown 
readily by the poorer people, who are least able to purchase them. 
Melons, pumpkins, squashes, cucumbers, and tomatoes, and some 
1 Bactrocera cucurbitae Coq. ; order Diptera, family Trypetidae. 
For a more extended account of the melon fly see Back, B. A., and Pemberton, C. E. 
The melon fly in Hawaii. U. S. Dept. Agr. Bui. 491. 64 p., 24 pi., 10 fig. 1917. This 
may be obtained from the Superintendent of Documents, Government Printing Office, 
Washington, D. C, for 25 cents. 
Note. — The manuscript of this paper was prepared for publication as a Farmers' Bul- 
;tin, but owing to the fact that it deals with an insect which has not yet been introduced 
into the continental United States it was considered more appropriate to issue it in the 
series of Department Bulletins. 
1 
18314°— 18— Bull. 643 1 
