LAKGE-CAGE EXPERIMENTS AT DALLAS, TEX., 1905-6. 

 LARGE-CAGE EXPERIMENTS AT DALLAS, TEX., 1905-6. 



49 



The work at Dallas for 1905-6 was planned especially to check 

 the results of the expermients at Keatchie which have been described. 

 The cage used (PI. IV, fig. 1) was divided into four sections, each 

 having a ground area of 100 square feet. In one section the natural 

 conditions of shelter were left unchanged (PI. IV, fig. 2). There 

 was practically no grass upon the ground, but the growth of stalks 

 was quite heavy. In the other three sections the shelter provided 

 (PI. V, figs. 1 and 2) for the weevils was arranged in such a way 

 that it might be possible to divide each section into two parts by a 

 middle partition. Unfortunately the first cold weather occurred 

 before the weevils could be placed in these sections, and it was neces- 

 sary to keep the weevils confined in boxes for several days until it 

 became sufficiently warm to render them active so that they might 

 find shelter in the cages. The weevils were liberated at approxi- 

 mately the center of each section and allowed to move in any direc- 

 tion they might choose. The object of this was to determine whether 

 particularly favorable rubbish might exert a special attraction for 

 the weevils. 



About three weeks after the weevils were liberated an examina- 

 tion was made of each section and the number of weevils crawling 

 actively upon the wire was determined. An examination of the 

 boxes from which the weevils were liberated and which had been 

 left undisturbed in the cages during this period showed that a large 

 mortality had occurred before the weevils really entered hibernation. 

 Table XXVI shows the principal points in regard to the beginning 

 of the experiments and the emergence of the weevils during the 

 following spring. 



Table XXVI. — Large-cage experiments in hibernation at Dallas, Tex., 1905-6. 



90317— Bull. 77—09- 



