F. L. Engledow 



101 



contains the results of some of the attempts, the notation for the types 

 of lateral floret being that of § II above. It is apparent that the relations 

 of the frequencies of the (B), (D)-awned, and (D)-pointed classes are 

 not constant, and the conclusion is that these classes are not constantly 

 and genetically different. In the light of the facts of fluctuation 

 mentioned in § II (B) above, the simplest view to adopt is that these 

 three classes are genetically identical, and that their apparent differences 

 represent the effects of environmental irregularities. Biffen (4) in the 

 case of the cross H. Schimperianum (6-row) x H. nutans (2-row) has 

 completely justified this view by proving that all'Fa plants which were 

 neither (A) nor (F) gave, in spite of eye differences inter se, F^ families 

 containing (A), (F) and various forms of the (D) type, i.e. that all such 

 F^ plants were heterozygous in respect to one factor, for form of lateral 

 floret. 



In consequence of this conclusion, the remaining F^^ were classified 

 by grouping all the (A) plants and the (F) plants, and combining the 

 . balance of the F^ under the name " heterozygote." Table II gives, in 



