No. 543] SHORTER ARTICLES AND DISCUSSION 153 



Da die Glieder der ersten Generation unmittelbar aus den Samen der 

 Hybriden hervorgehen, wird es nun ersichtlich, dass die Hybriden je 

 zweier differirender Merkmale Samen bilden, von denen die eine Halfte 

 wieder die Hybridform entwickelt, wahrend die andere Pflanzen gibt, 

 welche constant bleiben, und zu gleichen Theilen den dominirenden tmd 



This may be translated as follows : 



Since the members of the first generation 11 arise directly from the 

 seeds of the hybrids, it is now evident that hybrids, for each pair of 

 differentiating characters, form seeds, one half of which develops again 

 the hybrid form, while the other half produces plants which remain 

 constant and in equal proportions receive the dominant and recessive 



Various terms have been applied to this law by different 

 authors, e. g., "Law of Disjunction," 12 "Law of Purity of Germ 

 Cells," 13 "Law of Separation of Characters in Crosses," 14 and 

 "Law of Dichotomy." 15 Generalized, the law may be stated in 

 the following form: 



In self -fertilized species an individual which is a hybrid with refer- 

 ence to a particular pair of characters tends to produce progeny one 

 fourth of which is of pure race like one of the parents of the hybrid, 

 another fourth of pure race like the other parent, while the remaining 

 half is hybrid, like the original hybrid itself," 18 that is, " from the inbred 

 heterozygote come dominants and recessives in the proportion of 3:1, 

 and only one dominant in three is pure, the other two being hetero- 

 zygote." 



The above statement is purely objective; 18 it states the results 



u De Vries, II.* Comptes rendus de I'academie des sciences, Paris, Vol. 

 130, 1900, pp. 845-847. 



"Castle, W. E., Proceedings American Academy of Arts and Sciences, 

 Vol. 38, 1903, p. 537. 



14 De Vries, H., Journal Boyal Horticultural Society, Vol. 25, 1901, 

 p. 243. 



"Davenport, C. B., Biological Bulletin, Vol. 2, 190 



"Spillman, W. J., "Application of Some of the ] 

 to Plant Breeding," Bulletin No. 165, 

 Dept. Agriculture, 1909, p. 9. 



" Punnett, E. C, < < Mendelism. ' » Cambridge, 1907, 



14 For this paragraph and the one immediately fol 

 indebted to Professor W. J. Spillman. 



