63 



Reports made by agents of this Bureau who have investigated the 

 habits of the weevil in Cuba and Mexico show that the native varieties 

 of cotton, including the tree and kidney cottons of Cuba and the tree 

 cottons of Mexico, are just as susceptible to serious weevil injury asi 

 are the cultivated cottons. In some restricted localities in Central 

 America the dwarf character of the cotton grown and the very open 

 method of cultivation result in the production of some staple, though 

 the variety of cotton grown is by no means immune to weevil attack. 



The practical application of these observations may be emphasized 

 still further by the statement that in spite of the frequent and careful 

 removal of weevils from these cottons during the entire season none 

 of the non-American varieties made a single boll of good cotton, so 

 great was the actual weevil injury to them, while American cotton with 

 the same treatment developed a large number of bolls. 



The results are still further sustained b}^ observations upon larger 

 areas of American and Egyptian cotton under field conditions in three 

 localities in Texas, no weevils being removed from either kind. At 

 Victoria, Tex., on August 26, 1903, an examination showed that 96 

 per cent of Egyptian squares were infested, while an average of 13 

 fields of American showed 75.5 per cent. At Calvert, Tex., on Sep- 

 tember 4, Egyptian showed 100 per cent infested, while the American 

 varieties growing alongside showed 91 per cent. Similar results were 

 found at San Antonio. Though growing in close proximity, the Egyp- 

 tian produced no staple whatever, while the American gave better 

 than an average yield in spite of the depredations of the weevil. 



At Victoria, in the experimental tract during 1904, three varieties of 

 Egyptian cotton (Mit Afifi, Janovitch, and Ashmouni) were tested side 

 by side with American varieties. The Egyptian varieties uniformly 

 failed to make a pound of cotton, while the American varieties aver- 

 aged 400 pounds per acre. 



In accordance with these observations, it appears that in developing 

 a variety of cotton which shall be less susceptible to .weevil attack, by 

 far the most promising field for work lies among the American varie- 

 ties, and of these the very early maturing kinds are most promising. 



The question of choice of different varieties for food was tested in 

 the laboratory by Dr. A. W. Morrill, by placing squares of two kinds of 

 cotton, American and Egyptian, in alternate rows in a breeding cage 

 (PL IX, Rg. 39), so lettered and numbered that each square could be 

 exactly located. Weevils were then placed so that they could take 

 their choice of these squares, and observations from 8 a. m. to 6 p. m. 

 were made upon the location and activity of the weevils. Though this 

 experiment was repeated four times no positive evidence was obtained 

 to show that weevils had any choice as to which kind of squares they 

 fed upon. Table XIV presents a summary of these results. 



