MUTATIONS, VARIATIONS, AND RELATIONSHIPS OF THE) OENOTHERAS. 33 



Fig. 11 .—Correlation in the buds of Oenothera lamarckiana. No. 04113. 

 Length of ovary subject, length of hypanthium relative. Coefficient of 

 correlation, 0.4719 ± 0.041.?. 



ters, as thickness of hypanthium and length and thickness of cone, the plants 

 here represented stand intermediate between those of a and c, and that the 

 mean length of hypanthium was even less than in either, though it should 

 have been expected 

 to be as great as 

 that of a ; in other 

 words, the speci- 

 mens oiO. lamarck- 

 iana which sprang 

 from a rubrinervis 

 parent had certain 

 characters interme- 

 diate between pure- 

 bred 0. lamarckiana 

 and O. rubrinervis, 

 and in length of 

 hypanthium they 

 were even less than 



those of the latter species. These plants were considered typical Oenothera 

 lamarckiana, not only by myself, but by others who are familiar with that 

 species. Here again, as in the rest of the data presented in this table, the 

 general validity of any conclusion reached may be questioned because of 

 the small amount 

 of data. 



Comparison of 

 the entries c and 

 d, representing the 

 variation in the 

 buds of two dif- 

 ferent pedigrees of 

 0. rubrinervis, 

 shows that only in 

 length of hypan- 

 thium and thick- 

 ness of cone were 

 the two lots 

 essentially alike 

 in mean value, 

 the means of the 

 other parts differ- 

 ing from each other by more than the sums of the probable errors. In respect 

 to variability, entry c shows considerably greater coefficients in every set of 



Fig. 12. — Correlation in the buds of Oenothera lamarckiana from Hilversum. 

 Length of ovary subject, length of bud-cone relative. Coefficient of correla- 

 tion, 0.6340± 0.0319. 



