li'lOj Frost: Mutation in Matthioia 161 



numbered I. ^liss Saunder's work shows tliat two flower-color factors 

 also belong to this linked group. 



The large-leaved type strikingly resembles Oenothera gigas, and it 

 may prove to be triploid in nuclear constitution. In that case segrega- 

 tion may be irregular and genotypically intermediate individuals may 

 be more or less frequently produced. 



It is probable that further study of these types will help to explain 

 the remarkable genetic behavior of Oenothera and of Citrus. 



LITERATURE CITED* 



Atkinson, George F. 



1917. Quadruple hybrids in the Fj generation from Oenothera nutans and 



Oenothera 'pycnoearpa, with F. generations and back- and inter- 

 crosses. Genetics, vol. 2, pp. 213-260, 11 tables, 1 diagr., 15 figs. 



Babcock, Ernest B. 



1918. The role of factor mutations in evolution. Am. Naturalist, vol. 52, 



pp. 116-128. 



Bartlett, H. H. 



1917. Mutation in MatthioJa annua, a "Mendelizing" species. [A review 

 of paper of same title by H. B. Frost.] Bot. Gaz., vol. 63, pp. 82-83. 

 Bateson, Wlliam, and Saunders, Edith R. 



1902. Experimental studies in the physiology of heredity. I. Experiments 

 with plants. Matthiola. III. Discussion. Eoy. Soc. London, Re- 

 ports to the Evolution Committee, vol. 1, pp. 32-87, 125-160, 15 

 tables. 

 Bateson William, Saunders, Edith R., and Punnett, Reginald C. 



1905. Experimental studies in the physiology of heredity. Matthiola. Roy. 



Soc. London, Reports to the Evolution Committee, vol. 2, iqi. 5-44, 

 tables. 



1906. Ibid. Stocks. Ibid., vol. 3, pp. 38-53, 4 tables, 2 figs. 



Bateson, William, Saunders, Edith R., Punnett, Reginald C, and Killby 

 (Miss) H. B. 

 1908. Experimental studies in the physiology of heredity. Stocks. Roy. 

 Soc. London, Reports to the Evolution Committee, vol. 4, pp. 35-40, 

 3 tables. 



Belling, John. 



1914. The mode of inheritance of semi-sterility in the offspring of certain 

 hybrid plants. Zeitschr. f. indukt. Abstam.- u. Vererbungsl., vol. 12, 

 pp. 303-342, tables, 17 figs. 



Blakeslee, Albert F., and Avery, B. T. Jr. 



1919. Mutations in the jimson weed. Jour. Heredity, vol. 10, ])p. 111-120, 



11 figs. 



* An asterisk prefixed to the date indicates that the paper cited has not been 

 seen by the present writer. 



