

MONTHLY LETTER OF THE BUREAU OF ENTOMOLOGY 
UNITED STATES DEPARTMENT OF AGRICULTURE 

Number 104 December. 1922. | 










TRUCK CROP INSECT INVESTIGATIONS HEMP RP 
Se JAN OA [9B8 & 
F. H. Chittenden, Entomologist in Charge 


Pe ee 
4 fed icy Y A 
Efforts toward the control of the Mexican bean#eette Ham 
been rewarded by the discovery of a very promising parasite. E. 
Graywood Smyth, who was sent by the Bureau in early May to Mexico 
to search for natural enemies of the bean beetle, has discovered a 
tachinid parasite that preys upon at least two species of Epilachna 
and seems to restrict itself to that genus. It was responsible for 
a very high fatality among Epilachna larvae in the Valley of Mexico 
and at Cuernavaca. In the neighborhood of 2,000 living puparia of 
this fly were sent to the Birmingham, Ala., laboratory and from this 
material Neale F. Howard, in charge of the laboratory, has succeeded 
in rearing one generation from native Epilachna larvae. A consider- 
able number of puparia are now being held in hibernation for the 
coming spring. 
In addition, Mr. Smyth found in Mexico two varieties of beans 
which show promise of resistance to the injurious attack of the bean 
beetle, one of them, a native edible white bean, known as "ayocote," 
which is cultivated on a fairly large scale in sections, the other a 
wild brown bean of the genus Phaseolus. The latter grows very abund- 
antly along streams in southern Mexico, climbing bushes and other 
vegetation, and the rather leathery foliage which it produces is very 
seldom attacked by the bean beetle, so that there is a possibility of 
the bean proving of great value for hybridizing with cultivated 
varieties to breed a resistant stock. 
C. H. Popenoe, E. Graywood Smyth, J. E. Graf, and D. E. Fink 
attended the meetings of the Association of Economic Entomologists at 
Boston during the holidays. 
SOUTHERN FIELD CROP INSECT INVESTIGATIONS 
J. L. Webb, Entomologist Acting in Charge 
Dr. W. D. Hunter spent several days in Washington during the 
month in connection with work of the Bureau and the Federal Horti- 
cuitural Board. 
