50 Lai cut and Sciui-Lalcnt Characters. 



These fii^nres arc presented oraphically in Fig. 6. 

 It will be seen that the normal curve is a symmetrical 

 one slightly depressed, however, over the ordinates of 

 the even numbers as a result of that symmetry which we 

 discussed above. The two other lines form half curves; 

 in both of them the apex coincides with one extreme. 

 The curve B, of the atavistic individual, is almost the 

 same as the curve which was the dominant one in the first 

 vears of my experiment when there were, as yet, no 6-7- 

 foliate leaves (p. 38). It is an ordinary half curve of 

 variation, which is characteristic of the half races of 

 semi-latent anomalies. The curve C is, however, re- 

 versed ; it displays the predominance of the racial char- 

 acter over the antagonistic one which is that of the 

 original species. It also shows the preference for sym- 

 metrical leaves. 



If atavistic individuals are used as seed-parents the 

 character of the race can be observed to vanish more or 

 less com])letely in a short time. I carried out an experi- 

 ment of this kind in the years 1896-1898, after the race 

 had reached its maximum development in 1894-1895 as 

 descri1)ed on page 38. Within the space of three gen- 

 erations this race has retrogressed so far that the plants 

 could no longer be recognized as belonging to it. For the 

 purposes of this reversed selection I chose, from the 

 plants which had borne a large number of 5-7-merous 

 leaves in 1895, those seedlings of wdiich the primary 

 leaves were single and the first leaves trifoliate. With 

 a few exceptions they had all developed occasional tetra- 

 pentamerous leaves by the middle of June. Three of the 

 exceptional ones were isolated before flowering, they sub- 

 sequently developed a few multipartite leaves. But when 

 their seeds germinated it was seen that they were not 



