ALTERNATIVE INHERITANCE 17 



F! (J Bagdad (white) X J Istrian (gold-yellow) ; produced all 

 white cocoons. 



F 2 Hyb. white X hyb. white; produced 77 white, 17 yellow 



cocoons. 



F 2 Hyb. white X hyb. white; produced 62 white, 15 yellow. 

 This latter example is also a Mendelian type of inheritance, but 

 the difficulty comes when it is compared with the former example. 

 The dominancy in one is with yellow; in the other with white. Note 

 that the two are reciprocal crosses. The dominancy has followed the 

 male. But necessarily so? For answer take another example from 

 this same Bagdad-Istrian series of crossings : 



F! c? Bagdad (white) X J Istrian; produced 31 white cocoons, 21 

 gold-yellow cocoons. 



F 2 Hyb. white X hyb. white; produced 57 white, 31 gold-yellow 



cocoons. 

 F 2 Hyb. white X hyb. white; produced 51 white, 18 gold-yellow 



cocoons. 

 F 2 Hyb. yellow X hyb. yellow; produced 86 yellow, 34 white 



cocoons. 

 F 2 Hyb. yellow X hyb. yellow; produced 42 yellow, 7 white 



cocoons. 

 F 2 $ Hyb. white X J hyb. yellow ; produced 40 gold-yellow, 26 



white cocoons. 



F 2 $ Hyb. yellow X J hyb. white ; produced 36 white, 29 gold- 

 yellow cocoons. 



Thus within a group of the same race crosses first one color and 

 then the other proved dominant or neither was dominant. But in all 

 cases the inheritance was strictly alternative, never particulate or 

 blended. 



Using other races of yellow cocooners and other races of white 

 cocooners various similarly conflicting results were obtained. For 

 example, in Italian Yellow X Chinese White, yellow was dominant ; in 

 Italian Yellow X Japanese White, yellow was dominant; in Turkish 

 and French Yellow X Bagdad White, white was dominant; in Istrian 

 Yellow X Chinese White, yellow was dominant; in Istrian Yellow X 

 Japanese White, yellow was dominant; in Persian Yellow X Chinese 

 White, yellow was dominant; in Persian Yellow X Bagdad White, 

 white was dominant ; in Italian Yellow X Italian White, approximately 

 half of the offspring of generation F x were white and half of them 

 yellow. 



