20 



large size. The shortest wiis 11 feet in height, while the tallest was 

 13 feet 4 inches, the average height being 12 feet -1 inches. The average 

 height of Hickory King grown in an adjoining row was al)out 8 feet 6 

 inches, while the average height of the Cuzco in the same field was 

 about 8 feet. Thus the hybrids on an aA'erage exceeded the female 

 parent in height by about 3 feet 10 inches and the male parent by 4 

 feet 4 inches. As stated under la, however, the Cuzco plants used for 

 this comparison were probabl}' somewhat below normal height, as the 

 result of their having been grown in pots in the greenhouses for a 

 time and then transplanted. Some of the hybrids of this series were 

 inbred about the 1st of September, when the first silks appeared, but 

 in all cases were too late to mature. The h3^brids in most cases started 

 to develop three to four ears, and these in all instances were very 

 high, the lowest on the several stalks varying from 7i to 8i feet from 

 the ground. 



In this experiment, as in experiment la, the Hickory King used as 

 the mother parent had not been cultivated previously under the 

 writer's direction, and was not definitely known to be pure, but as in 

 that case, and for the reason there given, the writer thinks there can 

 be no doubt that the four purplish kernels and the three kernels with 

 purplish-black spots produced on the original crossed ear, and which 

 were shown to be hybrid kernels by growing them the next j^ear, 

 must be interpreted as cases of undoubted xenia. In this experiment 

 also, as in la, many pure white kernels showing no indication of xenia 

 proved to be hybrids. 



Exj>erirne7it lOa^ lUch/ry King 9 X Cuzco No. 759 $ . —The plant of 

 Cuzco No. 759 froui which the pollen was taken was grown from a 

 dark plumbeous- colored kernel like that shown in PI. I, figs. 3 and 4. 

 A small well-tilled ear resulted, the kernels of which almost all showed 

 xenia in the plumbeous or heliotrope-purple color imparted to the 

 seeds, the color being limited to the aleurone layer of the endosperm, 

 as in PL I, fig. 32. The color varied greatly in density and distribu- 

 tion in the different kernels. Some were dark plumbeous or helio- 

 trope-purple at the apex and extending down to the middle of the 

 sides, but fading to nearly white below. Others were nearly white at 

 the apex, but plumbeous below on the sides. A very few^ were white 

 throughout like the mother parent. The character of the starchy 

 endosperm was also much modified, xenia showing as plainly in this 

 reward as in the color. Such kernels contained nuu-h more of the 

 soft, opaque, white, starchy matter, and less of the hard, horny, trans- 

 lucent matter, or corneous endosperm, than the typical kernels of 

 Hickory King, this character being clearly derived from the male 

 parent, the Cuzco, in which the endosperm is almost entirely lacking 

 in hard corneous matter. A fibrous, striped surface-appearance is 

 shown in many of the kernels, a character which, so far as the writer 

 is informed, is not shown by either of the parent races. (PI. 1, fig. 



