65 



H. Dwscheutos) were ^rown and an effort made to see whether weevils 

 would feed upon either the leaves, buds, or seed pods. In no case, 

 however, did they live on any of these for any considerable time, 

 though they fed slightly upon some of the parts. Hibernated weevils 

 starved in an average time of about 4c days with leaves of either okra 

 or Sunset Hibiscus. The buds and seed pods were not formed at that 

 time, : 3 could not be tested. Weevils of the first generation, which 

 had fed upon no cotton, were placed upon Sunset Hibiscus, and these 

 starved in an average of 3 or 4 days. First generation weevils, which 

 had fed for a few da^^s on squares, were placed upon leaves, buds, and 

 seed pods of Hibiscus vesicarius. Though the}^ fed a little, all starved 

 in an r verage of about 5 da3^s. A lot of first-generation weevils, fed first 

 for se 'era! days with squares, were given leaves, buds, and seed pods of 

 okra. More feeding was done by this lot than by any other, all parts 

 being slightly attacked. These weevils lived for an average of 7 days^ 



Numerous other plants, including sunflower (Ilelianthus annuus)^ 

 bindweed {Convolvulus repens)^ the slender pigweed and the spiny pig- 

 weed {Amaranthus Jiyhridus and A. spinosus), and western ragweed 

 {Amh'osia jpsilostacliya)^ and various other species of weeds and 

 grasses which occur more or less frequently around cotton fields were- 

 tested, but in no case was feeding noticed except in the case of weevils 

 supplied with pieces of the stem of sorghum, the stems of which were 

 cut into short lengths and some of the pieces split lengthwise. Upon 

 the exposed, juicy pith weevils fed considerably, but they did not 

 puncture through the hard stem to obtain the juice. The sweet sap 

 found in the pith sustained weevils for some time in the laboratory,, 

 but where obliged to puncture the stem, as they would be in the field^ 

 they would never attack sorghum, except possibly freshl}^ cut stubble. 

 Among the many plants tried, therefore, none has been found to show 

 an}^ capacity for sustaining the lives of weevils in the field in the 

 absence of cotton. 



During the summer of 1904 a number of other plants not closely 

 related to cotton were tried, but upon none of them would the weevils- 

 even attempt to feed. 



The question of the original food plant of the weevil has received 

 considerable attention from this Bureau, the investigations made in 

 Cuba being particularly thorough and conclusive. In that island some 

 varieties of cotton grow wild and are perennial. After most careful 

 search Mr. E. A. Schwarz wrote in the spring of 1903: "There is not 

 the slightest doubt, in my opinion, that the original and only food 

 plants of the weevil are the varieties of Gossypium and here in Cuba 

 the variety known as kidney cotton." The investigators of the 

 Bureau of Entomology have given special attention to the possibility 

 of the boll weevil breeding on other plants than cotton. Throughout 

 the investigations of Prof. C. H. T. Townsend in southern Texas and 

 16780— No. 51—05 5 



