The Endosperm in Inheritance 155 



cross (corneous pollen and floury ovule), the F, genera- 

 tion was all floury. This result certainly suggests 

 maternal inheritance, for in both cases it is the character 

 of the ovule parent that is transmitted, while the pollen 

 parent seems to have no effect. If it is assumed that 

 this is a case of maternal inheritance, similar to the 

 four-o'clocks of Correns, with their diseased cytoplasm, 

 two problems are encountered: (i) to prove that this 

 behavior is not due merely to parthenogenesis; (2) to 

 discover the mechanism to explain maternal inheritance 

 in this case. 



In the first place East established the fact that there 

 was no possibiUty of parthenogenesis. Continuing his 

 investigation he inbred the Fi generation in each case 

 and examined the F^ progeny. If we are deahng with a 

 case of maternal inheritance, what should the F2 genera- 

 tion show? It should be exactly the same as the Fi 

 generation, for in true maternal inheritance a race will 

 go on forever breeding true to the maternal character, 

 whether it is self-pollinated or cross-pollinated. If this 

 had been a case of true maternal inheritance East 

 should have obtained the following situation: 



Floury X Corneous Corneous X Floury 



F, Corneous Floury 



F2 Corneous Floury 



etc. etc. 



Actually, however, he obtained the following result: 

 Floury X Corneous Corneous X Floury 



F, Corneous Floury 



F2 3 Floury \ Corneous 5 Corneous 5 Floury 



