VARIATION AND HEREDITY 133 



Crest in poultry. 

 Rose comb and Pea 



comb. 

 Extra toes. 

 Broodiness. 



Absence of crest. 

 Single comb. 



Normal four toes. 

 Absence of this 



instinct. 

 Banded shell. 



Unbanded shell in 

 wood-snail. 



Plants 



Dominant character. Recessive character. 



Peas : — 



Tall stems. Dwarf stems. 



Yellow cotyledons. Green cotyledons. 

 Brown-skinned seeds. White seeds. 



Round seeds. 



Wheat: — 



Absence of awn. 

 Rough and red chaff. 



Keeled glumes. 

 Flinty endosperm. 

 Susceptibility to 

 rust. 



Barley: — 



Two-rowed ears. 



Nettles: — 



Markedly dentate 

 leaves. 



Wrinkled seeds. 



Presence of awn. 

 Smooth and white 



chaff. 

 Rounded glumes. 

 Floury endosperm. 

 Immunity to rust. 



Six-rowed ears. 



Slightly dentate 

 leaves. 



So far we have stated facts — the results of 

 experiment — but Mendel also suggested an 



