MICHAEL, A 'MARKED" DOG AND SHORT IN FRONT LEGS 



The standard of the breed calls for a white animal with pigment in only two places — eyes and 

 nose. But many dogs carry a diluted pattern in the coat — the faint spots can be seen on 

 the back — and many of them in addition show an outcrooping of color on the head, 

 Michael's "mark" being on and around the ear. This does not disqualify a bull terrier, 

 but is considered a defect. The colors of the mark are black and tan, indicating that 

 the breed was originally a tricolor one (black, white and tan) and has been steadily selected 

 for whiteness. As a fact, it originated in a combination of white bulldog or "mastiff " 

 (sic) and black-and-tan terrier. (Fig. 15.) 



that the standard requires what may 

 be termed a special albinism, in that 

 there should be no pigmentation except 

 in two places, the eyes and nose, and 

 that pigmentation should be as nearly 

 jet black as possible. The breed is an 

 old one and cross breeding has been 

 rather rare since it is heavily penalized 

 by "faults" in the offspring. 



Color spots when they do appear are 



often about the head and may be black, 

 black with tan edge, or tan. In 

 addition to the above "marks" or 

 colored hair, there are often so-called 

 "skin spots" which are hidden by the 

 outer coat, and are then disregarded. 

 A "mark" is not a disqualification in 

 the show ring as indicated by the marked 

 dogs that have become champions. 

 It is, however, generally undesirable.^ 



^ A spotted pattern, similar to that on the dogs, is found in a great many mammals. By 

 selection it can gradually be reduced, in which case it disappears first from the body and last of all 

 from the head (head and ears in mice; eyes, ears, and nose in guinea-pigs; eyes in rats; ears in 

 cattle; head in rabbit). It can never be controlled absolutely, however, because it is apparently 

 due very largely to developmental differences, as well as to inherited factors. Hence there is no 



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