R. K. Nabours 



159 



(c) In order to try out more completely the behaviour of the 

 heterozygotes derived from the crossing oi' leuconotus and leucothorax, 

 a leuconotus male from the second generation of an extracted leuconotus 

 culture (Exp. I, F3) was mated to a leucothorax female from the second 

 generation of an extracted leucothorax culture (Exp. I, Fs). The F^ 

 result was twenty-five adults, all leuconotus-leucothorax (BG). These 

 leuconotus-leucothorax heterozygotes were inbred and gave in F. the 

 following progeny (Table IV (c), Fj) : 



Actual Numbers 

 Expectation 



Leuconotus 



(£) 



5 



7-0 



Leuconotus- 

 leucothorax 

 {BV) 



17 

 15 



Leucothorax 



i'-i 



7-5 



This result is in perfect accord with the other results, showing that 

 the first parents were homozygous, and that the Fi heterozygotes 

 behaved in a regular Mendelian manner just as did the exactly similar 

 leuconotus-leucothorax (BG) heterozygotes in Exp. I. 



(5) Results from the matinf/ of heterozygous individuals -with one or 

 the other of their homozygous parent forms. 



Experiment V. (a) A leuconotus-leucothorax (BG) male fi-om 

 Exp. I, Fs (Table I, F,) was mated to a leuconotus (B) female sister, 

 and they gave in F^ (F^^) the fijllowing results (Table V): 



Actual Numbers 

 Expectation 



Leuconotus- 

 leucothorax 

 (BC) 



20 



20 



Leuconotus 

 (C) 



20 

 20 



Fi (Fi) 



Expectation 

 Actual Numbers 



Parents (Fs) 



20 



20 



• 



BC 



TABLE V. 



20 

 20 



• 

 B 



I 



I 



• 



BC 



BC Table I 



(Fs) 



(a) 



B 



Extract 

 TaLile I 



(^3) 



67 -.5 

 66 



C 



I 



c 



E.xlracL 

 Table I 



B = leuconotus. 

 C = leucothorax. 



(b) 



67-.5 

 69 



BC 



I 



• 



BC 

 Table I 



(^3) 



^1(^4) 



Parents (F3) 



11—2 



