294 Colotir and Marhmgi^ in Pedigree Hereford Cattle 



factor segregates, independently of other pigmentation factors, in the 

 simple ratio of 8:1, or really 1:2:1. Dominance is not in all cases 

 quite complete, so that the RR and Rr classes are not always easy to 

 distinguish with certainty. It is possible and even probable that the 

 factor for normal colouration has a modifying, or partially inhibiting 

 effect on the full somatic expression of that for " red eyes," so that a 

 normally marked red-eyed beast would not have such well-marked eyes 

 as a dark-necked red-eyed one, though both would transmit the red- 

 eyed factor in equal purity to their offspring. 



IV. Pigmented Nose. 



Pigment sometimes appears on the nose in Hereford cattle in quan- 

 tities varying from a mere spot or two up to a completely dark nose. 

 All forms of dirty nose are objected to by breeders, but brown spots 

 alone are not considered so bad as black, or "blue" (dilute black). Very 

 often an examination of a dark nose will show that both pigments are 

 present, this being perhaps a commoner t3^pe of dirty nose than either 

 pure black or brown. My observations concerning the inheritance of 

 brown pigment on the nose are insufficient to justify any conclusions 

 being formed. More information has been collected concerning black, 

 and black and brown combined. The first point that appears is that 

 this form of dirty nose is usually found accompanying that deep rich 

 coat colour known as claret. Out of 41 Herefords examined, which were 

 of this tint, 15 had pigment on the nose, and 26 had clean noses. But pig- 

 ment on the nose can occur independently of the " claret " coat, as I have 

 met with two pale brown, or yellow-brown animals that had well spotted 

 noses. These were a cow called Olive Oil (see PL VII, fig. 7) and her 

 bull calf Oliphant. As this cow was without a trace of the fashionable 

 plum tint, and the marks on her nose were particularly black, it shows 

 that the pigmented nose is not necessarily correlated with a claret coat, 

 and the factors for the two characters can segregate independently, 

 yet there appears to be some association between them, as out of 11 

 "yellow" coated animals examined the two mentioned above were the 

 only ones showing any trace of colour or marking, the rest having 

 perfectly clean noses, though in the case of claret-coloured cattle the 

 proportion rises to more than half. 



I have mentioned that black and brown pigments are often combined 

 in the dirty nose, and I have notes concerning the inheritance of such 

 a type of nose through a pedigree of three generations. This pedigree 

 is fully set out in the accompanying diagram, and from it, it will be seen 



