480 



THE AMERICAN NATURALIST [Vol. LIII 



that self is recessive to spotting and that color is re- 

 cessive to solid-white. The principle is suggested that 

 there is a quadruple allelomorphic series:— TT^, solid- 

 white; w"\ much spotted; w^, little spotted; and w, self, 

 with dominance in the degree of decreasing pigmenta- 

 tion. Crosses of white to self and of spotted to self would 

 ])e of value in checking this principle. Any one white cat 

 might throw besides white either much spotted, little 

 spotted, or self; a much spotted might throw besides 

 much, either little or self, and little should throw little 

 or little and self. If three distinct types were produced 

 from any one white or spotted cat crossed to numerous 

 self cats, this would demonstrate modifiers of consider- 

 able importance or disprove the hypothesis of allelomor- 

 phism suggested. 



Attention should be called to an interesting but unex- 

 plained relation that exists between yellow- and white- 

 spotting. "Self" tortoiseshells have yellow hairs closely 

 intermixed with non-yellow. This makes it very difficult 

 to determine degree of ticking in such animals. Tortoise- 

 shells with restricted white-spotting tend to have yellow 

 separated into patches, while further extension of white 

 separates yellow and non-yellow areas still more. Sep- 

 aration of yellow into patches appears not to be corre- 

 lated with amount of yellow. 



General Summary of Inheritance of Coat-Color in 

 Cats 



It may be of interest to summarize very briefly the 

 genetic* data thus far collected on coat-color in cats. 

 Eatios are not significant since fraternities from homo- 

 zygous dominants and heterozygotes are included 

 together. 



Maltese dilution, w, is presumably a simple recessive 

 to intensity, M. Intense by intense have produced 41 in- 

 tense Tntt'iisr !)>• dikite have produced 37 intense and 23 

 (lilntc. Dilntr 1)\ dilute have produced 18 dilute. 



Solid- white, W, evidently acts as a simple dominant 



