1914] . CURRENT LITERATURE 191 



Crosses of Oenothera. — Gates 10 reports the results of various crosses 

 between Oenothera grandiflora and a variant of Oenothera rubrinervis of 

 DeVries which he has described previously under the name Oenothera rubri- 

 calyx. He finds rubricalyx pigmentation (R) dominant to the type of pigmenta- 

 tion found in rubrinervis (r), and he believes this difference to be due to a single 

 Mendelian factor, though his proof does not seem convincing to the reviewer. 

 Assuming this to be the case, however, the discovery that various Fi individuals 

 produce F 2 ratios running from 3:1 to nearly 10:1 is very interesting, par- 

 ticularly as the same phenomenon appeared in the segregation of tallness from 

 dwarf ness. The author says these results are " inexplicable on a Mendelian 

 basis," and reverts to that familiar piece of biological sarcasm, the word " pre- 

 potency," as an explanation. Unquestionably there is a chance that these 

 odd ratios may lead to a distinct genetic advance when they are finally worked 

 out, but the word " inexplicable" is a little hasty, since it may be pointed out 

 that some of DeVries' dwarf mutants (0. nanelld) have been shown to be 

 infected with a micrococcus. 



The crucial proof that mutation is independent of hybridization, which 

 the author feels he has obtained, came from four aberrant plants which oc- 

 curred among the hybrids. Two combined characters of the DeVriesian mutant 

 semilata with characters of grandiflora, and two combined features of lata with 

 features of rubricalyx. One plant out of the four was examined cytologically, 

 and its cells were found to contain 15 instead of 14 chromosomes. This fur- 

 nishes definite proof, it is said, that the lata (or semilata) foliage and habit 

 results from the presence of an extra chromosome. 



A large portion of the paper is taken up with general Mendelian criticism 



character. It is somewhat reminiscent of the windmill 



acrimonious 



rected 



of Mendelians," of course without any citations whatever, and tilted at with 



gusto and satisfaction. — E. M. East. 



Cruciate-flowered Oenotheras. — Bartlett 11 has discussed certain species 

 of the much studied genus Oenothera. Nuttall named O. cruciata from its 

 linear petals, and thus the character of linear or narrowly oblong petals in the 

 genus, as contrasted with broadly obovate petals, has come to be known as 

 4t cruciateness." The origin of this character is under discussion, and Bartlett 

 believes that it has originated in several lines of descent. As a consequence, 

 he regards O. cruciata, as it has been ordinarily interpreted, as an aggregate, 

 which should be resolved. After determining the real type of O. cruciata, he 



10 



Breeding 



tion are independent phenomena. Zeitschr. Ind. Abst. u. Yererbungslehre 11:209- 

 279- 1914- 



11 Bartlett, H. H., An account of the cruciate-flowered Oenotheras of the sub 

 gem Onagra. Amcr. Jour. Bot. 1:226-243. fi&- 2 - pl$- 19-21. 1914. 



