6 PLANT-BUGS INJURIOUS TO COTTON BOLLS. 
conducting field observations, much credit is due Mr. J. P. Conduit 
and Mr. J. A. Vaughan, of the Tlahualilo Agricultural Company, 
Tlahualilo, Durango, Mexico. Mr. B. F. Butler of the same com- 
pany, manager of the Hacienda San Fernando, Lerdo, Durango, 
Mexico, furnished valuable information concerning the comparative 
grading of the cotton staple at infested and uninfested sections of 
the Laguna district. All of the investigations reported in this 
paper were conducted by Doctor Morrill, except where special credit 
has been given in the text. Of the original text figures, numbers 
2, 3, 4, 5, 6, 10, 11, 15, 16, 17, and 18 were drawn by Mr. J. F. Strauss, 
of this Bureau, while the remainder are the work of the author. 
W. D. Hunter, 
In Charge of Southern Field Crop Insect Investigations. 
