LETTER OF SUBMITTAL. 
U. S. DEPARTMENT OF AGRICULTURE, 
DIVISION OF ENTOMOLOGY, 
Washington, D. C., February 27, 1891. 
Sir: I have the honor to submit for publication Bulletin No. 24 of 
this Division. It consists of a preliminary report upon the special in- 
vestigation of the Cotton Boll worm (Heliothis armigera Hiibn.) which 
was authorized by Congress in the bill making appropriations for the use 
of the Department for the fiscal year 1890-91. 
Respectfully, 
C. V. RILEY. 
Entomologist. 
Hon. J. M. Rusk, 
Secretary of Agriculture. 
