Heredity 161 



of which the Indian corn is the most conspicuous example 

 (Fig. 43), there is double fecundation, both the embryo and 

 endosperm being fertilized, and hence if the male parent 

 contains dominant characters, they will be seen immediately 

 because of the cross-fertilized endosperm. This is called 

 Xenia and has been carefully worked out by de Vries, 

 Webber, 1 and others. 

 Mendel's numerical results. 2 



In the experiments conducted by Mendel with peas the 

 relative numbers obtained for each pair of differentiating 

 characters are as follows : 



Experiment 1. Form of seed. From 253 hybrids, 

 7324 seeds were obtained in the second trial year. Among 

 them were 5474 round and roundish and 1850 angular, 

 wrinkled ones. Therefore, the ratio 2.96 is to 1 is de- 

 duced. 



Experiment 2. Color of albumen. 258 plants yielded 

 8023 seeds, 6022 yellow and 2001 green ; their ratio, there- 

 fore, is 3.01 to 1. 



Experiment 3. Color of seed-coats. Among 929 

 plants, 705 bore violet-red flowers and gray-brown seed- 

 coats ; 224 had white flowers and white seed-coats, giving 

 the proportion of 3.15 to 1. 



Experiment 4. Form of pods. Of 1181 plants, 882 

 had them simply inflated and in 299 they were constricted. 

 Resulting ratio 2.95 to 1. 



Experiment 5. Color of unripe pods. The number 



1 Bull. 22, Div. of Veg. Phys. and Path., U. S. Dept. of Agric., 1900. 



2 The following is taken from a translation of Mendel's article as given 

 by Bateson, and slightly revised. See Bateson-Mendel's "Principles of 

 Heredity," Appendix. 



M 



