27 



bo puvo. The nuiulx'r of rases in which tlio red dont was usod and 

 oavo no indication of the red color as xonia strongly suggests that the 

 other cases were errors or due to other causes, and that the rule that 

 no character outside of the endosperm can be shown as xenia holds 

 here as in other cases. Further evidence on this point is furnished by 

 the experiments of McCluer, where Cranberry corn, in which the 

 color is in the pericarp, was used in crossing with other varieties. 

 He sunnnarizes his results as follows: 



Color, wliere it is ti character of the kernel and not of the seed coat, tends very 

 stronirly to i>ass from one variety to another. The j)ecnliar color of the Cranberry 

 dill not seem tu affect the other white varieties to which the pollen was applied. 

 The ('ranl)erry owes its color to the seed coat entirely; the kernel is white, and the 

 variety is classiMl as a white corn.' 



SWEET COKN CROSSED WITIt SWEET CORN. 



Experiment loh. StoweWs Evergreen 9 X Blaeh Mexican $ . — A small, 

 poorly tilled ear resulted, on which about two-thirds of the kernels 

 were bluish black like the male parent, the color being limited to the 

 aleurone layer, and the pericarp in both races being uncolored and 

 hyaline. The kernels developed were rounded and quite different 

 from the normal StowelFs Evergreen, but this was doubtless due to 

 the few whicli matured on the ear. (PI. II, tigs. 10 and 11.) The color 

 imparted to the kernels in this case is pro])ahly due to xenia, though 

 the seed of the moth(M- parent had not been previously grown under 

 the writer's control, and so can not definitely be claimed to have been 

 pure. Dark blue-black corn is not commonh^ grown, however, and 

 is not very liable to be found as an impurity in the common races sold 

 by seedsmen in the United States. 



Experiment 36a, Black Mexican 9 X StoweWs Evergreen $ . — A small 

 ear resulted, on which almost all of the kernels were apparently typ- 

 ical Black Mexican. Eight kernels were whitish, as if possibly affected 

 by the cross, the bluish-black or plumbeous color of the endosperm 

 being absent. Whether this can be considered as a case of xenia can 

 not be told without further experiments. 



DENT CORN CROSSED WITH FLINT CORN. 



Experiment 37 a^ Iowa King 9 X Gilrnan Flint $ . — A fair sized 

 ear developed with yellowish- white kernels having a large proportion 

 of ver}^ hard corneous endosperm similar to the Flint parent. All of 

 these kernels seem to clearly show xenia, but the purity of the female 

 parent was not definitely known. 



In Kellerman and Swingle's experiments four ears of white dent 

 races were crossed with pollen of yellow or brown races of flint. Two 

 ears showed xenia in producing yellow kernels and two remained 

 unaffected. 



1. McCluer, Corn crossing. 111. Agr. Exp. Sta. Bui. 21 (1892), p. 84. 



