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MASS. EXPERIMENT STATION BULLETIN 185. 



The Inheritance of Pigments. 



Thus far we have dealt with the inheritance of pigment patterns without 

 reference to the particular colors involved. All the pigment patterns 

 studied carry many different colors. So far as we have been able to see, 

 there is no relation between the behavior of pigment patterns and the 

 pigments themselves. We will now consider the manner in which the 

 several pigments behave in inheritance. 



It is evident that there are two classes of pigments found in the varieties 

 of colored beans used in these experiments. One class appears as some 

 shade of red or purplish red, and is found in Red Valentine, Golden 

 Carmine, Mohawk and similar colored varieties. This pigment is readily 

 soluble in water, as shown by laboratory tests and indicated by the readi- 

 ness with which such seeds fade when exposed to the action of dew and 

 rain in the field. The light reds, such as Red Valentine, take on the 

 purplish color when treated with alkali, and the purplish reds of Mohawk 

 change to a bright red in acid solutions. The former are unchanged in 

 acid solutions and the latter in alkaline solutions. These reactions indi- 



Table XI. — Crosses of Blue Pod Butter ivith other Self-colored Varieties. 



