4o6 



The Journal of Heredity 



fruits above doubles. The remainder 

 of the trees represented in the tal)le 

 produced their last crop in 1915. In 

 all of these varieties the per cent of 

 multiple fruits is hij^h, with Oran^'e 

 riing and October Kll)erta the hij^hest, 

 having ninety-two per cent abnormali- 

 ties ranging from twins to quintuples. 



The trees infested with crown gall 

 were naturally of lower vitality and in 

 less vigorous condition, and produced 

 quite generalK- a lower per cent of 

 multiple faiits. On the other hand, 

 the most \igorous trees and those with 

 (he hea\iest set of fruit had the highest 

 per cent of multiples. 



CAUSES OF ABNORMAL PRODUCTION 



In view of the data available it 

 appears that this abnormal condition 

 was brought about by en\'ironmental 



influences causing disturbance in the 

 reproductive organs of the peach. The 

 severe climatic conditions and lack of 

 moisture in the soil resulted in a dor- 

 mant and unproductive state on the 

 part of the trees lasting for several 

 \ears, and upon the return of fa\orable 

 conditions the sudden vigor stimulated 

 them to unusual functioning which 

 gave rise to a tendency to overproduc- 

 tion. The trees have produced normal 

 fruit in previous years, and will, un- 

 doubtedly, do so in the future unless 

 affected l)y similar external influences. 

 The proper coml)ination of en\iron- 

 mental factors which brought about 

 this phenomenon may not soon occur 

 again, yet this case proved the deep- 

 seated influence of such factors even 

 on the morphology of the reproductive 

 organs in the peach. 



HERITABLE CHARACTERS OF MAIZE 



X. ZEBRA STRIPED LEAVES^ 

 M. Demerec 



N. Y. Stale College of A gric id hire, Ithaca, N. Y. 



ZI'.HRA stripefl leases ofVorn were 

 first obser\ed in the summer of 

 1920 by Professor l--merson in two 

 Vi generation families resulling from 

 a cross between Kight-row sweet corn 

 and a small po|) corn that had been 

 profluced by a cross of California Rice 

 with Tom Thumb pop. The material 

 was turned over to the writer for fur- 

 ther study. In the summer of 1921 it 

 was noted that among the corn grown 

 for genet ical studies some other fami- 

 lies, distantly if at all related to the 

 foregoing, were also segregating for 

 zebra striping. This is an indication 

 that the character had probably been 

 present in the material for some time, 

 but had not been noticed before. In 

 the same simimer apparently the same 

 type of striping was found in the|)rog- 

 eny from three selfed plants. Tlu" 



seed for one of these plants was ob- 

 tained during the previous >-ear from 

 the Breck Seed Company of Boston. 

 It was a yellow dent corn, Minnesota, 

 No. 13. The seed for the two other 

 plants was obtained from the Vermont 

 Experiment Station. One sample was 

 marked Freak No. 4 and the other 

 Freak No. 5 on account of the pecul- 

 iar shape of the ears. Intercrosses 

 were made to And out if those ajipar- 

 ently like characters were gcneticalh- 

 identical, but these tests have not been 

 completed. 



DESCRIPTION OF ZEBRA STRIPING 



Zebra striping does not show in the 

 early seedling stage. It belongs to the 

 group of chlorophyll characters in which 

 the normal amount of chloro|)lnll 

 diiuinishes with the age of the plant. 



• I'apcr .\(j. yn, I >([).ii tiiHMt (jt I'l.inl Hm-ding, Cornell University, Ithaca, N. V 



