JOURNAL OF AGRICULTURAL RESEARCH 
DEPARTMENT OF AGRICULTURE 
Voe. I Washington, D. C., November io, 1913 No. 2 
THE OCCURRENCE OF A COTTON BOLT WEEVIL IN 
ARIZONA 
By W. Dwight Pierce, 
Agent and Expert , Investigations of Insects Affecting Southern Field Crops, 
Bureau of Entomology 
The preliminary announcement by Mr. O. F. Cook, of the Bureau of 
Plant Industry, in February, 1913, of the occurrence in Arizona of a 
weevil resembling the Mexican cotton boll weevil, appears at this time 
to have been an announcement of considerable importance. In com¬ 
pany with Mr. Harold Bell Wright, Mr. Cook found this weevil breeding 
in the bolls of a wild shrub known as Thurberia thespesioides in Ventana 
Canyon, Santa Catalina Mountains, Arizona. 
In May the writer obtained a large quantity of bolls of Thurberia from 
Mr. W. B. McCleary, of the Bureau of Plant Industry, who collected 
them in the lower part of Stone Cabin Canyon, Santa Rita Mountains, 
Arizona. This material was very heavily infested by the weevil. 
During August Dr. A. W. Morrill, State Entomologist of Arizona, 
together with the writer, located this weevil in Ventana Canyon, Santa 
Catalina Mountains, and in Sawmill Canyon, Santa Rita Mountains, 
breeding commonly upon the same plant. 
A close examination of the material received early in the year disclosed 
many minor points of difference from the usual form of the cotton boll 
weevil, Anthonomus grandis Boheman. The Arizona form averages 
slightly larger and is a little more robust. The punctation of the male 
beak is a little more pronounced, and the sculpturing throughout is 
slightly stronger than in the Texas form. The scaly vestiture approaches 
a golden color, while in the Texas form it is usually grayish. The sides 
of the prothorax in front are rarely emarginate, while the emargination 
is usually very noticeable in the Texas form. Minor differences also 
appear in the shape of the teeth on the legs. All in all, the adults of the 
Arizona weevil present an assemblage of characters differing from the 
eastern form sufficient to suggest a new species. 
Journal of Agricultural Research, 
Dept, of Agriculture, Washington, D. C. 
Vol. I, No. 2 
Nov. 10, 1913 
