Nos. 620-621] COLOR IN AVENA CROSSES 



377 



similar to that obtained in the F 2 generation have been 

 brought together and the results are here shown for the 

 three classifications made on the second generation. 



The relation between color and percentage of awns of 

 these three families mentioned above is shown in Table 

 IV. 



Here again, it is apparent that the black oats ranged 

 all the way from awnless to 100 per cent, awns as do the 

 gray oats. The yellow oats, on the other hand, are 

 grouped near the lower percentage classes. Two indi- 

 viduals, however, exhibited about 50 per cent, of awns, 

 one being in class 40 to 49, one in 50 to 59. It may be 

 that these will be found to be grays instead of yellows. 

 However, in general, the tendency is for the yellows to 

 exhibit only a few awns. This is in accordance with the 

 results obtained on the second generation and substan- 

 tiates the conclusion drawn from the study of that ma- 

 terial. It may be worth while to call attention here to 

 the segregation as to color which fits the hypothesis more 

 closely than does the material of the second generation. 

 The segregation exhibits what is without doubt a 12 : 3 : 1 

 ratio. The observed numbers are 230 black : 57 gray : 21 

 yellows while the expected numbers are 231.00 blacks : 

 57.75 grays : 19.25 yellows. 



The relation between color and pubescence on these 

 third generation families is shown by Table V. 



TABLE V 



Showing the Segregation as to Colok and Pubescence of Three F, 

 Families grown from Heterozygous F 2 Plants. Series 687 

 Pubescence 



Here it is clear that again all the black oats are pubes- 

 cent while the gray oats fall into the three classes. The 



