MEXICAN" BEAN BEETLE IN THE SOUTHEAST. 



23 



8. It will be noted that the survival of beetles was slightly less than 

 15 per cent in each cage. 



The total period of emergence was about two months — from April 

 5 to June 6. The maximum emergence occurred between April 19 

 and May 6 in the two cages, which is more than a week later than 

 the previous year. The majority of the beetles observed through- 

 out the winter in nature (Table 6) had left hibernation by April 26, 

 and all except one had issued by May 10. 



Table 8. — Hibernation at Birmingham, Ala., winter of 1921—22. 



CAGE 1. 



Beetles collected. 



Beetles removed. 



Date. 



Number. 



Date. 



Number. 



Sept. 21 

 Sept. 22 

 Sept. 23 

 Sept. 24 

 Sept. 29 

 Sept. 30 



Total. 



500 



800 



6,000 



5,200 



600 



4,700 



Apr. 5.. 

 Apr. 12. 

 Apr. 22. 

 Apr. 27. 

 May 3.. 

 May 5. . 

 May 6. . 

 May 8. . 

 May 12. 

 May 19. 

 June 2. . 

 June 6 . . 



17,S00 



Total 



Percentage survival . 



100 



85 



220 



180 



300 



753 



301 



267 



102 



203 



73 



16 



2,600 

 14.61 



CAGE 2. 



Oct. 1 



Oct.2 



Oct. 3 



Oct.5 



Oct.7 



Oct. 8 



Total 



4,700 

 1,350 

 3,000 

 3,200 

 1,800 

 4,000 



18, 050 



Apr. 4.. 

 Apr. 5.. 

 Apr. 12. 

 Apr. 17. 

 Apr. 19. 

 May 4.. 

 May 8. . 

 May 20. 



Total 



Percentage survival. 



100 

 314 

 186 

 1,036 

 213 

 453 

 231 

 105 



2,638 

 14.61 



HIBERNATION AT CHATTANOOGA, TENN. 



The Mexican bean beetle reached Chattanooga, Term., early in 1921, 

 and reproduced rapidly that year. It had not become abundant, 

 however, by fall. In October, 18,000 beetles, collected at Birming- 

 ham, Ala., were placed in hibernation on Lookout Mountain in 

 Tennessee, in a cage and with materials for protection similar to those 

 used at Bhmingham, Ala. The altitude of this mountain is more 

 than 2,100 feet above sea level, and the latitude is 35° 21' N. Beetles 

 were removed when the locality was visited and the results are given 

 in Table 9. The survival in this cage was lower than in the others, 

 probably because the beetles were not removed regularly. No 

 attempt was made to estimate the mortality due to starvation in the 

 spring, but it is believed that a higher percentage of survival would 

 have been obtained if the cage had been observed daily. Of the 

 adults placed in this cage, 9.7 per cent survived the winter. The 



