R. K. Nabours 



155 



(3) The interbreeding of hetero^i/gotes. 



Experiment III. All the crosses of heterozygous individuals with 

 homozygous ones and the inbreeding of heterozygous ones had given 

 results that could hardly be interpreted in any other way than by 

 assuming that the heterozygous, or hybrid, individuals gave gametes 

 alternatively, one representing the male parent and the other the 

 female parent. Not a single exception to this rule had been noted. 

 A few crosses had been made between different heterozygotes from 

 nature whose constitutions were not ascertained till their Fi and F^ 

 progeny gave the clue (Exp. I, Table I, and Exp. II (a), (6), (c), 

 Table II (a\ (6), (c)). At this time it seemed that some crosses 

 ought to be made between different hybrids of known constitutions ; 

 so the following crosses were made simultaneously : 



(a) A leucothorax-luteolineatus (CE) male from Exp. II (c), /'i 

 (Table II (c), F^) and a leuconotus-leucuthorax (BC) female from 

 Exp. Ill (c), Fi (Table IV (c), F^) were crossed, and th<3y gave in the 

 F, generation (F„ Table III (a)): 



Actual Number; 

 Expectation 



Leucotliorax 



9 

 9-5 



Leuconotus- 



leucothorax 



(BC 



9 



9-5 



Leucothorax- 

 luteolineatus 

 (CB) 



7 



9-5 



Leuconotus- 

 luteolineatus 

 (BE) 



13 



9-5 



TABLE III. 



£xi^>ectation 

 Actual Nuiiilxji's 

 ^1 



9-5 

 9 



C 



9-5 

 9 

 • 

 BC 



9-5 



7 

 • 

 CE 



9-5 

 13 



• 

 BE 



45 

 52 



CE 



L_ 



45 

 36 



• 

 BC 



45 



44 



f 



BF 



45 



48 



f 



EF 



Pcll'Cllt.S 



6^ 



CE 



From Table 



llic){F,) 



BC 



From Table 



lV(c)(/\) 



6* 



CF 



From Table 



II(c)(/V) 



9* 



BE 

 From Table 



n(b)(^i) 



F, 



I'arciit.^ 



(a) 



(b) 



Expectation 

 Actual Numljers 



21-5 

 18 



BE 



21-5 



23 



t 



CE 



21-5 

 21 



• 

 BC 



21-5 

 24 



• 



E 



I 



10 

 12 



BC 



1 



10 

 11 



BE 



10 

 CI 



10 



10 1 



• f 



El BE! 



Fi 



Parents 



C3« 

 CE 



From Tabic 



B = leitconotus. 



(c) 



BE 



l-'rom Table 



n(b)(F,) 



6^ 



CE 



From Table 



n(c)(/',) 



$ t Parents 

 Bl 

 Oroup 

 culture 



C = lt'V£othora.v. 



F = rafi'olineatas. 



(e) 



E=luteolin€atu*. 

 idgroHOtatus. 



