EMEKGENCE FROM HIBERNATION, 1907. 



75 



Table XXXVII. — Chronological arrangement oj sectional records showing relative sur- 

 vival at Dallas, Calvert, and Victoria, Tex., 1906-7 — Continued. 



VICTORIA. 



Character of shelter and food. 



Weeds and grass 5 inches; stalks left. 

 Weeds and grass 5 inches; stalks 



removed 



Weeds and grass 4-5 inches; stalks 



cut, left 



Moss, bark, chips, etc.; no food 



Griiss and weeds 5 inches; stalks 



removed 



Stalks pulled, left; grass and weeds 



5 inches 



Grass and weeds 10 inches; stalks 



pulled and left 



Weeds and grass 2 inches; stalks 



pulled and left 



Ground bare; no food 



Bollsa 



Total and average . 



Date of 

 last 

 emer- 

 gence. 



1907. 

 May 11 



May 15 



May 11 

 June 15 



May 6 



Apr. 28 



May 23 



...do.... 



May 11 

 Mar. 4 



Basis 

 number 



of 

 weevils. 



2,375 



2,375 



2,-375 

 2,850 



2,850 



2,850 



2,850 



2,850 

 1,088 

 (a) 



22,463 



Total 

 v/eevils 

 emerged. 



201 

 105 



134 



674 



362 



449 



374 



588 



139 



2 



3,028 



Percent- 

 age of 

 survival. 



8.46 



4.42 



5.61 

 23.65 



12.70 



15. 86 



13.19 



20.63 



12.78 



Rank of 

 section in 

 survival. 



o Three bushels of bolls on the surface, and 3 bushels covered with 2 inches of earth. 



The results of this work are exceptionally striking in the case of the 

 Dallas record. The Calvert record ranges between that of Dallas and 

 Victoria in regard to the clearness with which comparative effects are 

 shown. In each case there is, however, a general tendency toward 

 more successful hibernation as the season advances after the middle of 

 October until the time when frosts occur. In the case of the Dallas 

 records there occurred an almost uninterrupted increase in percentage 

 of survival with each date upon which experiments were started. 

 The apparent exceptions are readily explainable by other facts than 

 the time of starting the experiment. Section 12, which ranged sixth, 

 received weevils collected at Brownsville, Tex., wdiich made it neces- 

 sary to ship for a long distance. During this shipment their food 

 supply became poor, and the weevils were undoubtedly much weaker 

 upon being placed in the cage than were those which had been col- 

 lected in the immediate vicinity of Dallas. Section 6 w^as not provided 

 with any shelter for the weevils, and the percentage of survival was 

 smaller on that account than in other sections started at about the 

 same date. Section 10, which ranged ninth, received only infested 

 bolls, upon and within which weevils were hibernating. From 

 October 13 to November 15, under approximately similar conditions, 

 the percentage of survival increased from 2.61 to 31.34. (See PI. 

 VII, figs. 2, 3.) A more forceful argument than this for the destruc- 

 tion of the food supply as early in the fall as is possible could hardly 

 be given. 



A combination of the records for those localities at which experi- 

 ments were started upon the same or approximate dates, grouping 

 them so that the chronological sequence is most clearly sho\\Ti, adds 

 additional emiDhasis to the statements which have just been made. 



