INHERITANCE OF COLOR IN PERCHERON HORSES. 



279 



matter which is wholly beyond determination. It has been dis- 

 cussed above whether these results show the effects of inbreeding 

 of blacks (p. 271). 



Gallon's law and Pearson's modification of it have both been 

 criticised by advocates of the Mendelian hypothesis (Castle, '03). 

 It is not included in the purpose of this paper to consider that 

 law except in incidental connection with Tables I., XV. and 

 XVI. 



TABLE XVI. 



SHOWING NUMBER OF GRAYS IN ANCESTRY OF 179 INDIVIDUALS, FOR THREE 



ANCESTRAL GENERATIONS. 



NOTE. a equals number in class ; b equals number of grays. 



ZOOLOGICAL LABORATORY, 



NORTHWESTERN UNIVERSITY, 



Evanston, 111., June, 1905. 



