THE ORIGIN OF GYNANDROMORPHS. 



49 



No. 3. February 1915. T. H. Morgan. Text-figure 34 (drawing) 



Parentage. — The mother was rudimentary and the father bar. 



Description. — The gynandromorph was about three-fourths male. The 

 right halves of the head and of the thorax were female, being larger in size, 

 having larger bristles and a larger wing, which was wild-type, and no sex- 

 comb. The right eye was heterozygous bar (female). The left eye was bar 

 of the male type and the left halves of the head and of the thorax were male. 

 The left wing was smaller, but not inidimentary. The abdomen seemed en- 

 tirely male, with a normal penis. This gynandromorph was tested as to 

 sexual behavior and was found to pay no attention to mature virgin females. 

 An account of this gynandromorph and the drawing have been previously 

 published. (Morgan, Am. Nat., V. 49, p. 240, April 1915.) 



Explanations. — An egg with a rudimentary X was fertilized by an X sperm 

 carrying bar. Elimination of the maternal rudimentary X occurred. Some 

 of the female 'cells were lost in cleavage, so that the individual is prepon- 

 derantly male. 



Text-figure 34. 



Text-figure 35. 



No. 2317. November 2, 1915. C. B. Bridges. Text-figure 35 (drawing). 



Parentage. — One X chromosome of the mother carried the genes for rudimen- 

 tary wing and fused veins, and the other X the gene for bar. The X chromo- 

 some of the father carried the genes for vermilion eye and forked bristles. 



Description. — The left side of the gynandromorph is male, with sex-comb 

 and rudimentary fused wing, the left side of the abdomen is male, but the 

 genitalia are female. The ocelli on the head are like those of fused, and the 

 head is therefore male. No sections were made. 



