292 



Proceedings of Indiana Academy of Science. 



pounds, with eyes intermediate in color between tlie parent types. If the 

 Kenes for these different eye colors are allocated at different levels f)n the 

 sex chromosome there should appear among the grandsons eyes of the wild 

 , type as a result of the phenomenon of crossing over. The evidence presented 

 from these combinations is consistant with that obtained from other tests 

 in showing that this does not occur. 



The nomenclature employed is that used in other publications for the 

 members of this system. — white w. tinged wt. buff wbu, eosin w^. cherry w*", 

 coral w'^o, blood wb, red W. 



The female is expressed by the formula XX, the male XO, consequently 

 the formula for a tinged eyed female is wtwtXX, a tinged eye male wtXO. 



The following tables give the results- of the combinations made between 

 the different members of this allelomorphic series. The genetic composition 

 of the parents (P), the children ( F, ), and grandchildren (F,) are expressed 

 in terms of the nomenclature stated above. The numbers indicate the num- 

 ber of flies realized from the different combinations. 

 1. Linkage of Buff oiid Tinged 

 (a) Buff 9 by Tinged cf. 



