10 



The Journal of Heredity 



scribed, while on the other hand, if evi- 

 dence is furnished that this F^ grain is 

 heterozygous for purple and for non- 

 purple (white), no violence will be 

 done to our mutation conception of the 

 origin of the chimera. 



SUMMARY 



Grains of hybrid corn are here re- 

 ported in which xenia occurs only in a 

 portion of the aleurone layer, others 

 having sweet patches in the starchy 

 endosperm. Evidence is furnished dis- 

 proving the theory of independent de- 

 velopment of the second pollen tube 

 nucleus and the endosperm nucleus. A 

 factor mutation occurring in a single 

 somatic cell, producing a chimera, is 

 offered as the more probable explana- 

 tion of the phenomenon. A certain F.^ 

 grain may furnish conclusive proof of 

 the hypothesis advanced. Instances 



are cited of the occurrence of similar 

 chimeras in several plant genera. 



LIST OF LITERATURE CITED 



Correns, C. : Untersuchen iiber die 

 Zenien bei Zea mays. Ber. d. Deutsch. 

 Bot. Ges. 1/. l&i'J. 



Webber, H. J. : Xenia on the Imme- 

 diate Effect of Pollen in Maize. U. S. D. 

 A., Div. Veg. Phys. and Path. Bui. 22. 

 1900. 



Norton, J. B. S. : Some Unusual To- 

 mato Variations. Proc. Soc. Hort. Sci., 

 1910. 



East. E. M., and H. K. Hayes: In- 

 heritance in Maize. Conn. A. E. S. 

 Bui. 167, 1911. 



Babcock, E. B., and F. E. Lloyd: So- 

 matic Segregation. Jour. Hered., Vol. 

 8, 1917. 



Babcock, E. B., and R. E. Clausen: 

 Genetics in Relation to Agriculture. 

 New York, 1918. 



The Effect of Cross-Pollination on Size, Color, Shape and Quality of the Apple^ 



W. H. Wicks, formerly horticulturist. 

 University of Arkansas, reports the re- 

 sults of investigation for three years of 

 the "Effect of Cross-Pollination on 

 Size, Color, Shape, and Quality of the 

 Apple." It is the second publication of 

 a series on apple pollination problems 

 begun at the Arkansas Experiment Sta- 

 tion in April, 1914. 



The necessity of cross-pollination of 

 the apple has been set- forth by investi- 

 gators, both in this country and abroad. 

 Considerable literature on this subject 

 has accumulated. Data collected, also, 

 by this station since 1914 show the ne- 

 cessity of cross-pollination. Growers are 



now aware of the importance of cross- 

 pollination and are planting commercial 

 apple orchards in alternate varieties. 

 More bees are kept each year by the 

 more progressive orchardists, as it has 

 been demonstrated that insects, espe- 

 cially the honeybee, are most beneficial 

 in promoting pollination. 



Where this occurs the question arises, 

 what is the immediate influence or ef- 

 fect of the pollen of the male parent on 

 size, color, shape, and quality of the 

 fruit of the female parent? This study 

 was conducted (during 1915. 1916, and 

 1917, in a typical commercial orchard 

 at Springdale, Ark. 



1 Monthly Bulletin of the California State Commission of Horticulture, October, 1918. 



