Inheritance of Colour in Horses. 57 
on the problem of the segregation of sex. 1 On crossing together 
the hybrids, then, as far as the horned character goes, the 
mating was similar to that originally made between the 
Suffolks and Dorsets, but the result was singularly different, 
for both horned and hornless rams and horned and hornless 
ewes were produced. 
So far we have considered each of these character-pairs 
separately, confining attention to either the coat colour or the 
horns. Taking them together we find that the black or white 
or Speckled individuals may be horned or hornless. These 
characters have thus entered into a new series of combinations. 
In the parent, white faces were associated with horns, but 
among the descendants of the hybrid are black faced indivi- 
duals with horns ; similarly, the white face of the Dorset type 
appears without horns. Were there any point in fixing these 
new breeds, it would probably prove an easy matter, for either 
white or black faces would in all probability breed true at 
once to these characters, and attention would have to be 
directed only to the horns. 
In this case, the fact that the hybrid male is horned and the 
female is hornless introduces a complication which has not 
yet been investigated. To test the purity of the forms appear- 
ing in the generation raised from the cross-breds, a further 
breeding test would be necessary. Crossing the hornless 
types with the pure Suffolk would, if the type was fixed, 
give nothing but hornless offspring, whilst if impure, horned 
individuals, as well as hornless, would result. Similarly, the 
horned types, if crossed with the Dorset, should always produce 
horned offspring if pure, or horned and hornless if unfixed 
with regard to this feature. 
Shorthorn- Aberdeen Angus Cross. — In cattle, the polled 
condition appears to be dominant over the horned, since in 
crosses between Shorthorns and the polled Aberdeen Angus, 
the resulting animals of either sex are polled or at the most 
bear small scurs in place of horns. Similarly the black colour 
of the Aberdeen Angus is dominant over the red of Shorthorns, 
whilst white appears to be recessive to the latter. 2 
Inheritance of Colour in Horses. — Actual experiments 
planned to trace the inheritance of the various characteristics 
have not yet been carried out, and in view of the cost such a 
research would entail, it is not likely that they will be for 
many years. Nevertheless data of the clearest kind are not 
wanting here, and the story of the inheritance of the chestnut 
colour of the coat is known with certainty. The facts have 
J From information received from Sir John Thorold, it appears that crosses 
between Galloways and Shorthorns are horned if males, and hornless if females. 
2 Cameron, Live Stock Journal, December 28th, 1906. 
