1929] SERVICE AND REGULATORY ANNOUNCEMENTS 105 
HOW TO RECOGNIZE FRUIT FLIES 
Larvw or Maggots 
Look in the fruit for slender, whitish, or pale-colored maggots that are stout 
behind and taper strongly towards the head end. These may be as little as 
one twenty-fifth or as much as one-third inch long, according to their age. 
Larvie with legs or with a plainly recognizable head are not fruit-fly larvae. 
Fruit-fly larvae have only two pairs of breathing pores or spiracles, one pair 
at the posterior end of the body, each half showing three narrow openings, the 
•other pair near the front end. True fruit-fly larvae have the posterior spiracles 
set flush with the end of the body ; other larvae which may be found in fruit 
have them set at the ends of protruding cylindrical tubes. These protruding 
tubes are important in separating fruit-fly maggots from those of scavenger flies. 
The drawings show the differences between true fruit-fly larvae (No. 1) and 
other fly larvae that may be found in fruits and vegetables in the southeastern 
United States (Nos. 2-5). If you find a maggot which looks like the top picture 
inside of or near a fruit, send it to your State entomologist for identification. 
Pupae or Inactive Stage 
Examine the surface of the soil beneath bearing fruit trees and sift the 
top layer of this soil, looking for stout elliptical, brown bodies about one-sixth 
inch long which resemble in general appearance swollen grains of wheat. 
Search for these in the bottoms of containers in which fruit has been stored 
•or shipped and in the beds of trucks or wagons which have been used in hauling 
fruit, and on or beneath the floors of buildings used for packing fruit or for 
storing it in bulk. Such bodies may be the puparia of the Mediterranean 
fruit fly. If you find anything that resembles such a brown "seed," send it 
to your State entomologist for identification. 
Adults or Flics 
The fruit fly adult is a small yellow insect with dark spots about the shape 
and ^ize of the common house fly, or somewhat smaller (about one-fifth inch 
long), which run- actively over the surface of the fruit and foliage. It has two 
thin wings which are not clear but instead show an irregular, colored pattern 
over most of the surface. The flies are very difficult to find on the trees, but if 
a suspicious looking specimen is caught, send it to your State entomologist for 
identification. 
Refrigeration of Infested Fruit not an Adequate Safeguard Against Spread 
of Fruit Fly a " 
« 
P. Q. C. A.— 231 May 22. 1929. 
Following the recent discovery of the establishment of the Mediterranean 
fruit fly in central Florida there has been a Large demand for some publication 
giving the life history, habits, and means of control of this pest. The mosl 
available publication on this subject is Bulletin 640, by Back and Pemberton of 
the Bureau of Entomology, entitled "The Mediterranean Frnit Fly." published 
in 1018 and based on some four years' studies of this pest In Hawaii. To meel 
the demand for information, this bulletin has been reprinted and widely 
distributed. 
The possibility of destroying the early stages of the Mediterranean fruit fly 
by refrigeration of Infested fruit is briefly discussed in this bulletin (p 36) and 
this discussion has encouraged the Idea that adequate refrigeration could be 
accepted as an alternative for destruction of frnit under suspicion of Infestation. 
These experiments were of a Laboratory or small-scale nature -not confirmed 
by commercial tests in bulk or under Bhlpping conditions — and were not deemed 
to be sufficiently convincing to warrant any movement of fruit from Hawaii to 
"This circular represented the status of Information on the subject at the time it was 
Issued. The determination which has more recently been mad.' thai fruits and vegetables 
can be carried with safety, namely, without freeclng, well below 82 i\. 1ms been made 
the basis of additional experimentation, with the remit of developing practicable means 
of killine; insect life in fruit, etc.. by the utilization of temperatures as low as 28* P. 
