Studies of the pink bollworm in Mexico /

wy Ase a i aU SS a8 SS ir hal Oh 64 sy 3 SCY 0 | 5 0) Kear 5 I er 28 | : INCEPTION AND SCOPE OF THE WORK !Since its introduction into Mexico in 1911 the pink bollworm?has established itself firmly in the Laguna district and has made its appearance in several less important cotton-growing sections in Mexico, as well as at several points in the United States.The United States Department of Agriculture began research work on the pink bollworm in the Laguna district of Mexico in 1918.The results of the work of 1918 and 1919 were reported by Loftin, Mc-Kinney, and Hanson.? After an interruption of one year the work was resumed in March, 1921, at a new station at Tlahualilo, Durango, Mexico, on a large cotton plantation.*In considering the results of the research work dealt with in this report, it must be recalled that the climate in the Laguna district (fig. 1) is very dry, the average annual rainfall being only about 8 1 This report is based on two years' work in the Laguna, conducted by the Federal Horticultural Board under the authority given, in the appropriation for the eradication of the pink bollworm, to investigate in Mexico or elsewhere the pink bollworm as a basis for control measures.This investigation has been conducted under the general direction of the chairman of the board and W. D. Hunter, a member of the board.In accordance with the policy established by this board with respect to any research work on insect pests which it becomes necessary for the board to conduct, the results of this investigation are presented as a contribution through and in collaboration with the Bureau of Entomology.The field and laboratory work has been under the charge of W. Ohlendorf, assisted at various times by the following agents of the Federal Horticultural Board: F.