300 Colour and Markings in Pedigree Hereford Cattle 



in one individual all the characters that have been dealt with in this 

 paper. 



Lest it should be thought that normal markings are always produced 

 by the combination of the W and Z) factors I may say there is undoubtedly 

 a special factor for the typical form of pigmentation, as many strains of 

 Herefords breed pure to it and never throw either dark or white varia- 

 tions. Were it otherwise, any and every line would be liable to produce 

 individuals both too white and too dark, which is not the case. 



Though the characters are inherited as clear and separate entities 

 there is some indication of association between purple (or claret) coat 

 colour and the dark nose, but this is certainly not complete, as badly 

 spotted noses have been met with on pale brown cattle. 



There are undoubtedly many other characters than those which have 

 been more or less dealt with which would repay study, some of consider- 

 able economic importance, as, for instance, the ability to put on the 

 maximum amount of flesh on the minimum amount of food. There is 

 some slight evidence that dark-coated cattle do not feed so quickly as 

 pale brown but put on their flesh more evenly, and that the "yellow" 

 feed faster, getting excessively fat^ but tend to become patchy and un- 

 even, the fat accumulating in lumps. As the evidence on these points 

 is not sufficient to be conclusive they are only mentioned here to show 

 that the study of heredity in this breed may have considerable importance 

 for the practical as well as the scientific man. 



The notes on the history of the Hereford breed show that the pig- 

 mentary characters are survivals from earlier times when no selection 

 was practised of colour or markings, and that the faults which appear 

 and reappear in the present day Herefords are not, as some breeders 

 believe, spontaneous variations, but due to Mendelian factors, carried by 

 apparently normal animals, which cause the characters concerned to 

 appear when a suitable combination of gametes gives them the oppor- 

 tunity. 



There can be no doubt that the modern Hereford has been evolved 

 from the old cattle found in the County of Hereford by a purifying 

 process, by selecting and selecting from what was originally most hetero- 

 geneous material, until the more or less homogeneous breed as we know 

 it to-day has resulted. 



That many if not most of our domestic breeds have been produced 

 in a similar manner can hardly be doubted. It is by selecting and re- 



^ It is stated (11, p. 120) that yellow mice are prone to get exceptionally fat. 



