298 



There seems no hope, therefore, of tindiiig a variety of cotton that will 

 not be attacked by it. 



If the weevil has another, an original food plant, as it must have 

 unless it has always fed on cotton, it will probably be found in the 

 Monclova region of Coahuila. No wild malvaceous plant could be 

 found in the regions visited, and the insect was not found on any other 

 plant than cotton. Information obtained from Monclova by Don Jesus 

 K. Kios, and communicated to me by letter, states that the insect has 

 never been known there on any other plant. 



Oviposition. — The weevils deposit their eggs first in the buds, which 

 are to be found within the squares. When the buds are all infested, 

 the females oviposit in the smallest bolls, then in the next largest, 

 until all are attacked that are still green. Judging from the egg-laying 

 habits of the genus, the female makes the hole in the bud or boll with 

 her beak, and then turning around, applies the tip of the abdomen to 

 the hole and deposits an egg therein. The same female may deposit a 

 considerable number of eggs. 



Appearance of an infested field. — As the weevils attack first of all 

 the buds within the squares, these usually die and drop off. Therefore 

 as soon as a field becomes well infested the presence of the insect can 

 be told at once by the fact that few or no blooms are to be seen on the 

 plants. A field may be in full bloom, but as soon as the insect gets 

 well spread over it and accomplishes its work hardly a bloom will be 

 seen. Soon after the squares are attacked they mostly turn yellow 

 and fall to the ground. 



Method of liihernatlon. — In one or two localities, during spells of cool 

 weather, I was able to make some observations on the hibernation of 

 the insect. 



It seems probable that a considerable percentage of the weevils win- 

 ter over in the bolls, in the cells which they have formed therein, either 

 as transformed weevils or as pup;e, or perhaps even as larvae. That 

 they may sometimes winter as larv* seems proven from the finding, 

 as above mentioned, of very small larv;e from the last of ISTovember 

 to the middle of December. They probably winter more frequently as 

 pupse, the latter having been found in the bolls as late as any examina- 

 tions were made, i. e., up to the middle of December, I^ewly trans- 

 formed adults were found plentifully in the bolls also during the 

 whole time of my investigations. 



But there are many other individuals belonging to earlier broods 

 which have issued and certainly will not reenter the bolls to hibernate. 

 The question is, where do these hibernate? In San Juan Allende, 

 where the fields are irrigated, there are many cracks in the earth, 

 caused by the rapid drying of the soil after irrigating. On a cold day 

 there I found that some of the weevils had crawled into these cracks, and 

 I think there is no doubt that many weevils crawl into them and under 

 clods of earth, under leaves, and other refuse to hibernate. I found 



