CLASSIFICATION AND INHERITANCE OF SMALL GRAINS 103 



TABLE XVII. INHERITANCE OF 4 INDEPENDENTLY INHERITED MENDELIAN 



CHARACTERS 



EXPECTATION OBTAINED 



Hooded, two-rowed, black, hulled 129.0 113 



Hooded, two-rowed, black, naked 43.0 43 



Hooded, two-rowed, white, hulled 43 . 42 



Hooded, six-rowed, black, hulled 43 . 56 



Bearded, two-rowed, black, hulled 43 . 45 



Hooded, two-rowed, white, naked 14 . 3 14 



Hooded, six-rowed, black, naked 14.3 15 



Hooded, six-rowed, white, hulled 14.3 14 



Bearded, two-rowed, black, naked . 14 . 3 14 



Bearded, two-rowed, white, hulled 14.3 17 



Bearded, six-rowed, black, hulled 14.3 14 



Hooded, six-rowed, white, naked 4.8 4 



Bearded, two-rowed, white, naked 4.8 6 



Bearded, six-rowed, black, naked 4.8 6 



Bearded, six-rowed, white, hulled 4.8 4 



Bearded, two-rowed, white, naked 1.6 1 



Totals 407.6 408 



Biffen found that there was a correlation between the black 

 color of the grain and the color of the palea in barley crosses. 

 Two Japanese workers, Miyazawa (1918) and So (1918), inde- 

 pendently, have found xenia when white-seeded varieties were 

 pollinated with black-seeded strains. 



Winter versus Spring Habit. Fruwirth (1909) lists spring 

 forms as dominant over winter as the usual mode of inheritance. 

 Gaines (1917) has obtained some winter forms from spring 

 crosses. In one cross he obtained 18.75 per cent, winter plants 

 and 81.25 per cent, spring plants in F 2 . Results were explained 

 by supposing one variety to carry a factor for winter habit which 

 was prevented from expression by an inhibitory factor. The 

 other parent was considered to lack both factors. 



Density of the Spike. Biffen (1907b) studied two crosses 

 between barleys which differ in the length of internode of the 

 spike. He found the FI nearly as lax as the nutans parent and 

 obtained curves in F 2 which indicated that there was one main 

 factor difference. Some of the more dense F 2 segregates were 

 tested in F z . From 65 plants so tested, 55 proved homozygous 

 for the dense condition. 



A biometrical study of inheritance of density 1 in a number of 



1 The average length of internode in the middle of the spike was obtained 

 by measuring the length of 10 central internodes, in millimeters, and point- 

 ing off one place. 



