EMERGENCE FEOM HIBERNATION, 1907, 



There is no indication that the time at which an experiment was 

 begun affected essentially the nature of the emergence movement. 

 The nature of the shelter, however, does seem to have an important 

 influence. This is most clearly marked in section 7, where the ex- 

 perimental shelter was Spanish moss. At Victoria after about the 

 12th of April more weevils emerged from this section than from all 

 others combined. This effect was less marked in the other localities, 

 but in each case there appeared to be a considerable delay in emer- 

 gence, due to the nature of this shelter. Owing to the fact that this 

 moss is living and growing wliile hanging in the cages or on the trees, 

 it takes up moisture as no other class of shelter does. The evapo- 

 ration of this moisture during the daytime then serves to keep the 

 mass of moss cool, and it is a well-known fact that the temperature 

 in bunches of this moss is several degrees lower than that of the air 

 dur'ng the daytime. Undoubtedly the lower temperature in the 

 moss is the factor which retards the emergence of the weevils so 

 decidedly. This factor may also be considered responsible for the 

 smaller activity of weevils shown in the moss sections during the 

 winter. (See Table XXXI, p. 63.) 



A somewhat more detailed statement of the emergence shows more 

 plainly the peculiar manner in which this was distributed during 

 1907. The figures are arranged for seven-day periods, and show the 

 average temperature conditions prevailing as well as the percentage 

 total of emergence occurring during each week. 



Table XLII. — Weekly summary of emergence records , showing relation to effective tem- 

 peratures, 1907. 



90317— Bull. 77—09 6 



a On February 28. 



