36 



THE ORIGIN OF GYNANDROMORPHS. 



eosin color. The right male eye was much lighter than the female left eye, 

 as is the rule with eosin even when diluted. 



Explanation. — Both egg and sperm carried the genes for eosin and cream. 

 Elimination of the paternal or of the maternal X occurred. Presumably the 

 autosome carrying the cream gene behaved normally as in all known cases, 

 but this case is not diagnostic, since the fly was homozygous for cream. 



w^ 



w^ 



w^ 



Text-figure 14. 



Text-figure 15. 



Text-figure 16. 



No. 1-5. A.M.Brown. April 9, 1914. Plate 2, Figure 4 (colored drawing) . 



Parentage. — The grandmother was homozygous for vermilion and hetero- 

 zygous for a lethal. The grandfather was eosin-miniature. A gynandro- 

 morph was produced by one of their wild-type daughters which had been 

 out-crossed to an eosin-miniature male. 



Description. — The right side was male throughout with an eosin (male 

 color) eye and miniatm-e wing. A sex-comb was present on the right foreleg. 

 The left side was entirely female, with red eyes and a long wing. 



Explanation. — A non-cross-over egg containing the wild-type X was fertil- 

 ized by an X sperm with genes for eosin and for miniature., Ehmination of 

 one of the maternal X's left the male parts eosin-miniature. 



w 



m 



w^ 



m 



No. 195. April 27, 1914. C. B. Bridges. Text-figm-e 15 (drawing). 



Parentage. — One X chromosome of the mother carried the gene for white 

 eye-color and the other X the genes for eosin and for lethal 4. The X 

 chromosome of the father carried the gene for sable. 



