No. 624] 



INHERITANCE OF IIULL-LESSNESS 



tarian. Here the hull-less form was used as the female 

 parent. The male parent possessed, as indicated by its 

 name, black glumes, and was a typical hulled oat. The 

 other cross was between Danish Island and HuUess in 

 which the hulled type was used as the female parent. In 

 each case the type was typical of the types as de- 

 scribed by the authors mentioned above. This form is 

 intermediate in that both kinds of kernels, hulled and 

 hull-less, are found on the same head. The type of pan- 

 icle resembles the hull-less parent more than it does the 

 hulled and may be considered as intermediate in type. 

 There are some spikelets with hulled and some with hull- 

 less kernels and also some with both hulled and hull-less 

 kernels. As a usual thing the hulled spikelets occur 

 towards the base of the panicle while the hull-less kernels 

 occur near the terminal spikelet which is almost inva- 

 riably hull-less if such kernels are present at all in the 

 panicle. 



There are fewer hulled than hull-less kernels on the 

 Fi types. The percentage of hulled kernels does not usu- 

 ally run very high. In Fig. 3 is shown a typical form of 

 Fi panicle of a cross between a hulled and hull-less oat. 



The Fg generation of these two crosses were grown in 

 the field in the summer of 1913. The plants were then 

 sorted into two groups, hulled and hull-less, or hull-less 

 like. All those plants having any indication of huU-less- 

 ness were placed in the hull-less class. The result of 

 these counts was as follows : 



Although the ratio deviates considerably from 3:1 it 

 indicates that this character behaves as a simple mono- 

 hybrid and that there is one factor pair concerned. In 



