SPIKELETS IN THE THIRD GENERATION 



Spikelets from diflferent F3 plants produced from 112 and 113. 



Redwood. (Fig. 4.) 



Drawings made by C. W. 



in length. It is of interest to state in 

 this connection that certain famihes in 

 later generations bred true to the condi- 

 tion where awns were developed at the 

 tip of the head only. These awns de- 

 veloped a length, however, equal to that 

 of fully awned plants. Of the 30 awned 

 plants only 6 developed black color like 

 the Marouani variety. More data are 

 being obtained, however, on this 

 character. 



The shape of the glume, that is, 

 whether pointed at the tip or having a 

 shoulder, segregated into 82 pointed 

 glumes : 28 non-pointed. 



Many of these F^ plants were tested 

 in F3. Owing to a poor stand, how- 

 ever, not enough plants were obtained 

 in all families to determine the inherit- 

 ance of the various characters. In 

 general, however, the results of the 

 third generation agree with the con- 



56 



elusions drawn from the material of 

 the second generation. 



Among the F2 plants were two (Nos. 

 112 and 113) which are of particular 

 interest in relation to the wild proto- 

 type question, and it is a description of 

 these and their progeny which we will 

 now consider. These two plants were 

 in many respects similar to the wild 

 wheat. They both possessed the brittle 

 rachis and long basal hairs or bristles. 

 One form was beardless, while the 

 other was partially bearded. The ker- 

 nels were longer than in the other 

 segregates and resembled the wild type. 

 The heads were flat, similar to the true 

 wild form. One of these forms. No. 

 112, is shown in Fig. 2. The one main 

 difference between the true wild wheat 

 and these segregates was that the spike- 

 lets of the segregates were somewhat 

 broader than those of the wild type. 



