25 



on s(n(Mi diffrrcMit plants were carefully inl)n'(l with their own pollen 

 and all of these, as well as some thirty ears (l«>veh)p(xl without inhreed- 

 ino-, showed the same intermediate cliaracters. The cobs w(>re white, 

 like Hickory Kino-, the male parent, but internu'diate in number of 

 rows, liavint;- from twelve to fourteen, while the mother parent has 

 ordinarily from twenty-four to twenty-six and the father parent from 

 eioht to ten rows. Some kernels were j'ellowish throughout and al)out 

 an equal numl)er white throughout, while some were yellowish on the 

 sides with white apexes. The difl'erent colored kernels were irreo^u- 

 larly mixed tot^ether on the same cob. 



Ki-]X'riii)('iit3J^(U Champion Wliitc Pcnii 9 X Iflchiry Kiii</ i . -V\\o, 

 ear which resulted was twelve-rowed, with a white cob. No effect of 

 xenia was visible unless the rather shorter and broader kernels were 

 caused by the pollen parent. This is doubtful, however, as the ear 

 was smaller than normal. 



Kxpci'niiciif Jy2((^ Learning YelUnr 9 X Cliaiiipion White Pearl $ . — 

 The ear which r(>sulted Avas eighteen-rowed, with a red cob. About 

 half of the kernels are yellowish throuji'liout. as in the normal Leaminj^ 

 Yellow (PI. I, figs. 80 and 31), and the others are yellowish on the sides, 

 with white apexes. This would seem to l)e a case of xenia, as both the 

 orange yellow color of the mother parent and the opaque white of 

 the father parent are in the endosperm, the pericarp and testa being 

 hyaline. There is a possibility that the seed of the Learning Yellow 

 used in this experiment mav have been iini)ure, but some of the 

 same seed grown at Washington in 1898 and in I81>t) came true, 

 though this is not positive evidence of the purity of the individual 

 kernels sown at Lincoln. The writer's experiments have not been 

 sufficiently extended in crossing the races of dent corn to determine 

 how generally xenia is shown. In the experiments conducted by Kel- 

 lerman and Swingle^ at the Kansas Experiment Station nineteen ears 

 of various white dent races were crossed with pollen of yellow dent 

 races. Of these, ten ears showed xenia b}- a change of color on some 

 of the kernels, while nine ears remained unafi'ected. Seventeen ears 

 of 3'ellow dent races were crossed with pollen of w^hite dent races, 

 and of these twelve ears showed xenia by a change in the color of 

 some of the kernels, while five ears remained unaffected. In these 

 experiments the seed of the various races used was not positively 

 known to be pure, and it is assumable that in some instances the 

 results obtained may have been due to previous crossing. It is 

 hardly probable, however, that all of the cases were due to this 

 cause. The mixing of white and j^ellow races of dent corn when they 

 are grown in adjoining fields is a matter of common observation with 



^ Kellerman and Swingle, Experiments in cross fertilization of corn. 1. c, and 

 Experiments in crossing varieties of corn. Second An. Rep. Kansas Agr. Exp. Sta., 

 1889, pp. 288-346. 



