54 



SELECTION IN CLADOCERA ON THE BASIS OF 



strains. Hence this comparison affords further evidence of an effect 

 of selection in Line 711. 



An effect of selection within Line 711 is not certainly established, 

 however, in view of the lack of sufficient confirmation from the same- 

 day-brood data. But these data were not very numerous and it is 



TABLE 19. Selection summary for Line 713. 



TABLE 20. Same-day broods. Summary of data for Line 713. 



Time period. 



Apr. 13, 1912- 



July 31, 1912 

 Aug. 1, 1912- 



July 31. 1913 

 Aug. 1. 1913- 



July 31, 1914 

 Aug. 1, 1914- 



July 7, 1915 



Strain. 



Plus.... 

 Minus . . 

 Plus.... 

 Minus . . 



Plus 



Minus . . 

 Plus.... 

 Minus . . 



2.7 



3.0 



14 7.1 



i-i 



5.4 

 14 13.8 

 1473.7 



100 

 KM 

 61 

 M 



19:i 



fftf 



Il 



400 

 tf7 

 fe4 

 9tM 



f,i>o 

 890 



3D.-) 



SM 



154.42 

 208.08 

 290.23 

 277.45 



+53 



10.42 

 73.53 



iM.Sf, fL'i'J 

 23.34 



77.37 5. 

 34.446.96 



difficult to ignore the very consistent differences between the two 

 strains after the first 4 months of the experiment. It is to be re- 

 gretted that no test series was conducted with this line. 



This case is very similar to that for Line 689, with which there 

 was a similar difference, but in the reverse direction. 



