412 BOTANICAL GAZETTE [may 



answer this, since I cannot say whether the particular grain which 

 gave the 0:9:7, although included in the red class, was noticeably 

 lighter than the other two. 



Class R"' indicated dark red (or purple ?). In the original count 

 these grains had been included with the red, but the intensity of 

 color was such that it demanded close scrutiny to distinguish 

 them from the purple. Four ears came from this class. Of these, 

 one gave 0:130:33, and the other three 0:200:0 (no exact count 

 was made of large homogeneous ears). The first was evidently 

 a 0:3:1, with an excess of red grains, while the others obviously 

 represented the ppRRCC genotype, the conclusions suggested being 

 similar to that of class R". 



Class P indicated faint purple, with the same significance as 

 R for faint red. This class gave three ears, as follows: 



No attempt is made at present to attach any significance to these 

 counts. In fact, it is felt that such counts are rather untrust- 

 worthy, since the color is frequently so faint as to lie at the very 

 limit of visibility. Sufficient at present that not so much as a 

 single light purple or light red was produced on these ears; only the 

 faint color of the parents was regularly produced. 



Class P' indicated light purple, and gave three ears, 142:47:52, 

 34:14:40, and 13:1:12. The first is probably a 9:3:4 and the 

 others 27:9:28 ratios. 



Class P" indicated dark purple, and gave one ear, 79:34:85, 

 probably a 27:9:28 ratio with an excess of red. 



The general conclusion from the preceding is that genotypes 

 may be distinguished, to a degree, on the basis of color intensity, 

 at least among red grains. One rather familiar with the material 

 should be able to pick out a given genotype in most cases, particu- 

 larly if he discarded intermediates, which the writer did not. 



Returning now to the faint grains, one is confronted by three 

 possible explanations: (1) these are grains, properly colored, in 

 which an inhibitor tends to lessen materially the intensity of the 



