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Scientific Proceedings, Royal Dublin Society. 



possible there may be some other explanation, as, for instance, that bay is 

 a diluted brown. Unfortunately we cannot experiment with horses as we 

 could with smaller animals. 



Extracting them from the three tables already given, the data in reference 

 to the bay and brown matings are as follows, greys being neglected : — 



With regard to this table, it must be remembered that probably all the 

 black Thoroughbreds are brown, and also that some black Shires are probably 

 brown and some browns black. 



When thoroughbred bays are mated with bays there are 270 chestnut 

 foals, 1 black, 1295 bays, and 125 browns. Assuming no misdescriptions, 

 this suggests that bay is dominant to botli chestnut and brown. This would 

 place brown between bay and chestnut. But in that case, in a mixed 

 population of browns, bays, and chestnuts, there ought to be a larger 

 number of brown foals than 125. The same remark applies to the Shire 

 figures. Again, when thoroughbred browns are mated with browns there 

 are 11 chestnut foals, 6 blacks, 78 bays, and 114 browns. This, on the 

 other hand, suggests that brown is dominant to both bay and chestnut. 

 But one of these suggestions must be wrong. The latter has the greater 

 semblance of correctness : that is that brown is dominant. Apart from the 

 suggestion that a diluting or saturating factor may connect bay and 

 brown, the figures in the table suggest the possibility that some bays may be 

 hybrids between chestnuts and browns : a suggestion wliich is upheld by 

 the breeding of brown with chestnut, viz., 205 chestnut, 17 black, 452 bay, 

 and 172 brown foals among Thoroughbreds. But again, if this be the 

 explanation, the bays when bred together ought to produce more than 125 

 browns, even assuming that a larger proportion of them are pure and not 

 impure bays. 



