VARIATION STUDIES IN BROME GRASS 
7 
altho it has not been carried far enough to permit of positive state¬ 
ments. If this splitting should continue to occur in succeeding genera¬ 
tions, we would consider the evidence sufficiently conclusive to call 
such splitting strains crosses or hybrids. Up to this point of our in¬ 
vestigation, however, these splitting strains have not been propagated 
by seed to determine this point, as other factors under observation 
have occupied the time at present available for this experiment. We 
have the seed of the splitting strains and when some other portions of 
Plate No. 6. 
the experiment are completed we expect to make plantings of these 
strains for genetic studies on these points. Until other work is com¬ 
pleted we will not be able to do this because time and land are both 
occupied with other phases of the subject. Suffice it to say that three 
crops of seed from the parent strain^ have been planted in progeny 
rows and that the progeny, with the exception of the splitting strains 
above noted, have bred true, indicating pure types. This phase of the 
work has gone far enough so that we feel justified in saying that it 
