DIRECTION AND FREQUENCY OF MUTATION ' 233 



BIBLIOGRAPHY 



Bridges, Calvin B. 1919 The developmental stages at which mutations 



occur in the germ tract. Proc. Soc. Exp. Biol, and Med., vol. 17, 



pp. 1, 2. 

 May, H. G. 1917 The appearance of reverse mutations in the bar-eyed race 



of Drosophila under experimental control. Proc. Nat. Acad. Sc, 



vol. 3, pp. 544, 545. 



1917 Selection for higher and lower facet numbers in the bar-eyed 



race of Drosophila and the appearance of reverse mutations. Biol. 



Bull., vol. 33, pp. 361-395. 

 MuLLER, H. J. 1920 Further changes in the white-eye series of Drosophila 



and their bearing on the manner of occurrence of mutation. Jour. 



Exp. Zool., vol. 31, pp. 443-474. 

 MuLLER, H. J., AND Altenburg, E. 1919 The rate of change of hereditary 



factors in Drosophila. Proc. Soc. Exp. Biol, and Med., vol. 17, pp. 



10-14. 

 TiCE, S. A. 1914 A new sex-linked character in Drosophila. Biol. Bull., 



vol. 26, pp. 221-230. 

 Zeleny, C. 1918 Germinal changes in the bar-eyed race of Drosophila during 



the course of selection for facet number. Proc. Indiana Acad. Sc, 



1917, pp. 73-77. 



1920 A change in the bar gene of Drosophila melanogaster involving 



further decrease in facet number and increase in dominance. Jour. 



Exp. Zool., vol. 30, pp. 293-324. 



