66 



H. E. EWING. 



TABLE III.- Continued. 



be about as great as before (in isolation 3), but here they went 

 together, and were not apparently affected by selection. In the 

 case of isolation No. 5, the final fraternal mean obtained was 

 exactly the same as the length of the first individual selected in 

 this subline. In the case of isolation No. 6, the final mean ob- 

 tained is found to be just one hundredth of a millimeter more than 

 the length of the first individual selected. The results of the 

 selections in these two check sublines are presented graphically 

 in Fig. 3, and the measurements and some other data obtained 

 are given in Table III. 



The results obtained for these six generations show no effects 

 of selection as far as size is concerned. What are the effects of 

 selection on other variable characters? 



Selections Made for Increasing the Length of the Antenna in 

 Comparison with the Length of the Body. Isolation No. 7. 



It was found that there was a variation not only in the length 

 of the antennae in comparison with the length of the body, but 

 also a great variation in the absolute length of the antennae of 

 the different individuals of a fraternity. Since the latter vari- 

 ation involves a complex character, the former was thought to 

 be best adapted for use in selection tests. In isolation No. 7 

 selections were made in an attempt to increase the length of the 

 antennae in comparison with the length of the body. They were 

 carried on for five generations. In every case the individual 

 with the longest antennae in comparison with its body length 

 was selected. The means (which express the ratios existing 

 between the antennal lengths and body lengths) obtained are as 



