94 
Journal of Agricultural Research 
Vol. I, No. a 
At least two species of parasites attack the Arizona “wild-cotton'’ boll 
weevil in the Santa Rita Mountains. One of these is a species of Ceram- 
bycobius and the other is a braconid. There are also some predators 
which attack it. 
Without further information it is idle to speculate as to the direction 
of the adaptation which has evidently taken place in Anthonomus grandis . 
If further research should locate this boll weevil breeding upon another 
genus of plants closely related to cotton, such as Eremoxylum, a genus 
of western Mexico, or upon one of the small wild species of Gossypium in 
Mexico, the direction of adaptation might be traced. Some of the 
Fig, 7. —Anthonomus grandis , var. 
thurberiae: A, Front leg; B, middle 
leg; C, hind leg. Much enlarged. 
(Original.) 
Fig. 8 .—Anthonomus grandis Boh.: 
A , Front leg; B , middle leg; C, hind 
leg. Much enlarged. (Original.) 
differences in the condition of the two varieties which show the range of 
adaptivity of the insect are as follows: 
The rainfall in the vicinity of Tucson, Ariz., for 40 years has averaged 
only 11.66 inches per annum, not reaching 3 inches in any month. July 
and August are the months of greatest precipitation. 
The rainfall at Victoria, Tex., for 20 years has averaged 36.63 inches 
per annum, with over 3 inches in seven months of the year. May is the 
month of greatest precipitation. 
The rainfall at Opelousas, La., for 17 years has averaged 57.12 inches 
per annum, with over 5 inches in six months of the year. July is the 
month of greatest precipitation. 
