434 Tricotyloits Races. 



VALUES OF THE OFFSPRING NUMBER OF 



P 4 PTTNT 



LOWEST MIDDLE HIGHEST SEED-PARENTS 



A 41% 31 45 67 16 



B 41*7^ 22 50 79 22 



Since these two cultures may be regarded as typical 

 of ordinary intermediate races, not subjected to improve- 

 ment by selection, I will give the full series of figures 

 for one of them (B). They are as follows: 



56 58 59 



W^ritten in this way the figures show, without any 

 further treatment, a group in the form of a curve the 

 apex of which was between 50 and 55%.^ 



I planted out the grandchildren of the plant B only, 

 and selected for this purpose (1897) the two parents 

 with 71 and 79%. The two cultures consisted of tri- 

 cotylous plants only, flowered on separate beds, fertili- 

 zation being left to the agency of insects, however, as in 

 ])revious years. The result of the determination of the 

 values in the spring of 1898 was as follows: 



HEREDITARY VALUES OF THE OFFSPRING NUMBER OF 



LOWEST MIDDLE HIGHEST SEED-PARENTS 



C 71% 34 62 74 23 



D 79% 48 64 79 24 



In comparison with the previous year, therefore, an 

 advance had taken place in the mean values but not in the 

 maximum. 



^ It is my custom to plot the harvest raised from each parent and 

 from each grandparent in this way. When grouped in this manner 

 the figures display the result very graphically; and immediately show 

 whether it falls outside the limits of observational error ; and whether 

 therefore the existence of differences between the individuals is 

 shown bevond doubt. 



