106 



GERT BONNIER 



(culture 729) there occurred a yellow female. Since her mother had 



the constitution -^- ^' " ^ and the father was a Bar male the only 



explanation seemed to he that she was an equational exception in the 

 sense of Bridges (1916 p. 120). She was crossed to a wild male (cul- 

 ture 745) from stock and she had really, as table 17 shows, inherited 

 the genes vermilion garnet and forked, i. e. she was an exceptional 

 female which carried one non-crossover X and one crossover X (cros- 

 singover between eosin and vermilion). A yellow female from 745 

 (table 17) was crossed to a miniature garnet male from stock and the 



TABLE 18. 

 Excerpt from table 5. 



output was: 98 regular females, 78 regular males, 8 exceptional fe- 

 males, and 3 exceptional males. 



Cut deficiency 9 The mother in the culture-bottle 445 (table 5) was 



an XXF-female of the constitution 



Sc ec ct V g f 



and she was as men- 



w« ll Ir 



tioned crossed to a scute broad echinus ruby tan forked male. 

 Among her 156 daughters there was one who was a scute echinus cut 

 female. There exist different possibilities to explain this, a) The egg 

 from which she originated may have been fertilized by a sperm w^hich 

 through mutation carried the gene cut. b) She may have been an 

 equational non-disjunction which carried one non-crossover X and one 

 X which was a crossover between cut and vermilion, c) The sperm 

 which fertilized the egg from which she originated may have been 

 deficient for the region of cut. Unfortunately she did not produce any 

 offspring whatever. But the mere fact that she showed herself to be 

 sterile is an indication that there was a deficiency since it is known 

 from other cases of deficiency that the females are of a more or less 

 pronounced sterility. 



Vermilion re-mutation. Among the female offspring from the cul- 

 tures 443 and 446 (table 5) there occurred a great number which were 



