164 BOTANICAL GAZETTE [February 



Genetical investigations of maize endosperm. — Fujll and Kuwada 24 

 have noted chemical differences between the red and the purple pigments of 

 the aleurone cells of maize, as indicated by differences in their solubility in 

 alcohol and in i per cent aqueous solution of sodium carbonate, and in their 

 color reactions with acids and alkalies. They state that the two pigments occur 

 either separately or together in the same seed. The latter fact, if substantiated, 

 should prove of interest to geneticists working with maize. The authors 

 suggest that variations in intensity of aleurone color may be accounted for in 

 part by the triploid nature of the endosperm, whereby reciprocal crosses may 

 differ in having either i or 2 doses of the dominant factor concerned and F 3 

 seeds differ in having either 1, 2, 3, or no doses. A cumulative effect of domi- 

 nant factors is assumed. They are apparently in error in attempting to 

 apply the same assumption to red color of wheat, where, so far as known 

 to the reviewer, the color is in the pericarp (diploid) rather than in the 

 endosperm. 



The genetical significance of the triploid nature of maize endosperm was 

 earlier pointed out by Hayes and East 25 in reporting results of crosses between 

 races with corneous and with floury endosperm. In reciprocal crosses between 

 flinty and floury varieties xenia did not occur. In F 2 a 1:1 ratio was obtained 

 whether the F t was self-pollinated or cross-pollinated by either the flinty or 

 the floury parent. A half of each class of seeds resulting from self-pollination 

 bred true and the other half again segregated. When Fi was cross-pollinated 

 by the flinty parent, all the corneous seeds bred true and all the floury ones 

 proved to be hybrid, while the reverse was true when Fi was crossed back to 

 the floury parent. Two hypotheses are offered to account for the results: 

 (1) the endosperm develops from the fused polar nuclei without double fertil- 

 ization, or (2) the two polar nuclei dominate the single second male nucleus. 

 A plant, pure for white endosperm but hybrid for endosperm texture, polli- 

 nated by a pure yellow corneous seeded race, gave a 1 : 1 ratio of corneous and 

 floury seeds, all of which were yellow, thus demonstrating double fertilization 

 and indicating the second hypothesis, that two doses of a factor for floury 

 endosperm dominate one dose of the corneous factor and vice versa. Crosses 

 of popcorn with both floury and dent types gave results more difficult of 

 analysis, owing in part, the authors suggest, to differences in seed size, but 

 two independent factor-pairs are indicated in at least some of the cases. It is 

 also thought that two factor-pairs are concerned in the inheritance of sharp 

 points characteristic of rice pop-corn. — R. A. Emerson. 



24 Fujn, Kexjiro, and Kuwada, Yoshinari, On the composition of factorial 

 formula for zygotes in the study of inheritance of seed characters of Zea mays L., 

 with notes on seed pigments. Bot. Mag. (Tokyo) 30:83-88. 1916. 



2 s Hayes, H. K., and East, E. M., Further experiments on inheritance in maize. 

 Conn. Agric. Exp. Sta. Bull. no. 188. pp. 31. pis. 8. 1915. 







