174 



E. W. SEYSTER. 



the ones that developed at 29. The extreme variates (high, 

 low) of the parents of the two sets are slightly greater in the 

 case of the set which developed at the lower temperature, but 

 as the greater difference here is only eleven facets, and as the 

 difference between the variates of the two sets of offspring is as 

 great as 145, it is certain that selection can play no great role 

 in determining the facet difference of the offspring here noted. 

 Experiment 5.7 (Tables XL, XII.). Parents of this experi- 



TABLE XI. 



EXPERIMENT 5. i. MALES. 



ment are the offspring of set 5.1 in experiment 5. In experiment 

 5.1, one set of offspring developed at 29 while another de- 

 veloped at 17. The male flies developing at 29 gave an 

 average which was 5 facets less than their parents which de- 

 veloped at the same temperature while the male offspring de- 



TABLE XII. 



EXPERIMENT 5. i. FEMALES. 



veloping at 17 had a facet average which was 127 greater than 

 that of the parents. The facet average of the female offspring 

 was ii greater for those developing at 29 and 120 greater for 

 those developing at 17, than that of the parents which developed 

 at 29. 



A part of the offspring from set 5.11 was continued for three 

 more generations at 29 (Table XIII.). The fifth generation 



