INHERITANCE IN RAGE HORSES 99 



dominant to bay. There are some facts, Mr. 

 Bunsow tells me, wliicli suggest that a brown 

 horse can carry brownness, bayness, and chestnut- 

 ness. This possibility leads us to consider the 

 gametic possibilities of a grey horse. If grey is 

 dominant to all other colours, as it appears from 

 Mr. Bunsow's pedigrees to be, then grey horses may 

 be of many gametic classes Some may carry black- 

 ness and brownness recessive, others blackness and 

 bayness, others brownness and chestnutness, others 

 roanness and brownness, and so on. Or, they may 

 even carry three or four different recessive colours 

 in their sex-cells. We may therefore expect that 

 when finally the offspring of all the different possible 

 matings of grey horses with those of the other 

 colours have been adequately noted, they will present 

 a polychromatic display. 



The fact described by Mr. Bunsow on p. 88, 

 of two horses which were born grey, a dominant 

 colour, and later turned brown, a colour recessive to 

 grey, is one which it is hoped, in the light of Men- 

 delian knowledge, will be more fully examined. 

 These two horses w^ere " Tsu Shima " and the colt of 

 1909 by " Misselthrush." 



At first sight this fact appears to be quite in- 

 consistent with any idea of dominance or of the 

 conception of the purity of gametes carrying 

 recessive characters. The phenomenon, however, 

 is not altogether new in Mendelian experiments. 

 In poultry two sorts of " whites " have been 

 detected. One of these is a recessive white and the 



