326 POMONA COLLEGE JOURNAL OF ENTOMOLOGY 



Cirilo Vidal and Sr. Procopio Alejia. These orchards were all kept moderately 

 clean and somewhat cultivated by order of the government several years 

 ago. In all the orchards visited, wherever there was any ripening fruit, the 

 dread fly was found in greater or less numbers depending on the amount of 

 fruit ripened. Decay had hardly progressed far enough to cause any extensive 

 dropping of fruit, so that statistics on this matter had to be gathered from 

 residents. Even at that early season, however, the infection was quite general, 

 although the worms were not far developed as yet. Inquiries from the packers 

 at the railroad station revealed the fact that a large percentage of the fruits 

 had worms but the fruit was shipped, nevertheless, to the Mexico City market. 



Some of the growers assured me that the pest is rapidly disappearing in 

 their section. Others, among whom was a very intelligent and well-to-do 

 grower, Mr. Chas. A. Aragon, were sure that the pest is decidedly on the 

 increase, and that the danger from its ravages is immense. 1 am not in 

 a position to state whether or not it is decreasing, but this n.uich can be 

 said with great emphasis — if it has decreased in the last few years, then it 

 must have been fearful beyond words a few years ago. 



After studying the habits of the insect in its various stages of existence, 

 the department of parasitology offered the following artificial means of com- 

 batting and possibly exterminating the pest. 



1. Gather each day all the mangoes, lemons and oranges which may 



have fallen from the trees and deposit them in a clean corner of 

 the orchard. 



2. Destroy all fruit thus accumulated at least once a week. 



3. It is preferable to destroy the fruit by burning, but it may be disposed 



of by burial, and when buried it should be covered with at least 

 fifty centimetres (twenty inches) of soil. 



4. As the same worm exists in the guava, this fruit should also be 



destroyed in the same manner. 



In a report to the Miilister of Agriculture in 1900 Prof. Herrera wrote; 

 "As preventive measures I advise the burning of all the early oranges, the 

 cleaning up of all the orchards, the substitution of wire fences for live hedges, 

 and the burning of all fruit which ripens prematurely on the trees. It is 

 very probable that the enforcement of these measures for two or three con- 

 secutive years in all parts of the Mexican Republic invaded by the maggot 

 would result in its total extirpation." And yet today the insect continues 

 its ravages apparently unchecked. Probably the first question to arise in 

 one's mind is: have these measures been thoroughly applied by all concerned? 

 Before answering this it might be well to see what it means to apply these 

 measures everywhere in the infested districts. (Fig. 122.) 



The usual intermixing of orange, mango and guava trees has already 

 been spoken of. It is very difficult, to say the least, to keep a place well cleaned 

 and cultivated which is covered in a most irregular fashion with various sorts 

 of trees. Another difficulty is in the existence of more or less wild trees 

 which are onlv occasionally visited for the fruit. The guava grows very com- 



