HIBERNATION AND DEVELOPMENT OF BOLL WEEVIL. 



13 



to a stalk the previous fall. During the present year (1904) but 1. 6 per 

 cent survived hibernation on the plots counted. This figure is open to 

 slight error, as upon this plantation there were possibly 20 acres of 

 cotton about a mile away, which were planted much earlier than was 

 most of the plantation. This early cotton was infested at the rate of 20 

 weevils to 100 stalks on May 31. It is evident that the weevils which 

 hibernated on the plantation as a whole had concentrated on this early 

 planting, but if the total number of weevils upon this early cotton had 

 been distributed over the whole acreage there would have been not 

 over 2^- weevils per 100 stalks or 2.5 per cent surviving hibernation 

 at the most. Two per cent would probably be very nearly correct. 

 At Victoria, Hunter and Hinds have shown that approximately 15 per 



vrtT«TkSr«or>Mt 



cOLi£itKon?!a. 



*B»"W 



Fig. 3. — Rainfall and temperature records of College Station and Victoria, Tex., for 1902-3, compared 



with normals. 



cent of late-developed weevils survived the winter of 1902-3 in hiber- 

 nation cages. The very careful records made by Mr. Teltschick by 

 hand-picking the weevils during the spring (see p. 59 of that report) 

 shows that this very closely approximates the number of weevils nor- 

 mally surviving under field conditions in Lavaca County, but that dur- 

 ing the last winter (1903-1) fully 30 per cent of the weevils, or twice as 

 many as usual, hibernated successfully. In 1900 Professor Mally's 

 records (1. c, p. 32) show that Mr. Kramer picked 2,000 weevils at 

 Booth, Fort Bend County, or 13 to 100 stalks, which would give at 

 least 13 per cent surviving the winter, in a latitude practically the 

 same as that of Vienna. It will be seen, therefore, that whereas 15 

 per cent may be considered an average of the number surviving 



