Little: Coat Color in Pointer Dogs 



245 



then black. That such is the case the 

 relative proportions of the three records 

 in the stud book seems to show. 



STUD BOOK statistics. 



Stud book statistics are all of them 

 open to the objection that, at their 

 best, they represent part of the truth 

 rather than the whole truth, in that the 

 animals recorded are not the total 

 count of offspring produced by any 

 mating, but are rather those that reach 

 saleable age or maturity and are reason- 

 ably close to the standard of the breed 

 to which they belong. Such circum- 

 stances bring about a somewhat dis- 

 torted view of the actual phenomena 

 of inheritance in this case, but if proper 

 allowance is made for probable inaccura- 

 cies it seems likely that stud book 

 records of a standard organization like 

 the American Kennel Club are accurate 

 enough to give valuable statistics. 



In collecting the data for this paper 

 certain points had to be considered. 

 Each mating of registered dogs was 

 recorded on a separate card and filed 

 according to the dam's registration 

 number. On this card the offspring of 

 the mating were recorded one by one 

 as they were met with. No mating was 

 used in compiling results unless it 

 contained two or more offspring. Fully 

 two-fifths of the pointers listed in the 

 American Kennel Club stud book are 

 from unregistered parents. None of 

 these matings were recorded, since they 

 were less valuable and less accurate in 

 nature than those of registered parents. 

 The earliest volumes of the stud book 

 (Vols. 1-10) were not accessible to me 

 from the same source as the later ones. 

 This is not of any great importance, 

 however, since the number of animals 

 included in them is not large and since 

 the chance of technical errors is un- 

 doubtedly greater in the earlier numbers 

 than in the later ones. 



lang's work with dogs. 



One of the few investigators to pub- 

 lish work on inheritance of dogs since 

 the rediscovery of Mendel's Law is 

 Professor A. Lang. Lang experimented 

 with a pair of Fl hybrid dogs which he 

 obtained through Herr Pfister-Kupfer. 



The dogs thus obtained by Lang were 

 black in color, and had been produced 

 by crossing a brown-spotted female, 

 somewhat hound-like in appearance, 

 with a pure-bred black Newfoundland 

 male. Fourteen puppies were thus pro- 

 duced, all of which were black in color. 

 This is excellent evidence that black 

 is epistatic to brown, thus coinciding 

 with the work of many investigators of 

 inheritance in mice, rabbits and guinea- 

 pigs. 



Lang wished to inbreed the Fl 

 animals in order to ascertain whether 

 or not alternative inheritance existed. 

 If such was the case, brown puppies 

 would reappear in the F2 generation. 

 He therefore mated together his two 

 Fl animals and obtained a litter of 

 eight puppies. Of these, five were black 

 and three brown, six to two being the 

 theoretical Mendelian ratio in this case. 

 This shows that in all probability, 

 black and brown, in dogs, will follow 

 the same order in inheritance that they 

 do in mice and guinea-pigs. 



A careful record of the extent of 

 pigmentation also revealed that solid 

 and spotted coat were, in all probability, 

 a pair of Mendelizing units as they are 

 in the other small mammals already 

 investigated. 



OBSERVED FACTS IN POINTERS. 



If one turns to the case of pointers as 

 recorded in the stud books, one finds 

 this same pair of characters, black and 

 brown, showing the same relation to 

 each other. In pointers, as in most 

 hounds and spaniels, brown is often 

 spoken of as "liver." The brown or 

 liver-colored dog is very distinct from 

 black or any of its modifications, such 

 as blue or gray. The nose and feet of 

 the liver-colored dog are pigmented with 

 rich chocolate brown pigment, with no 

 trace of black pigment present.' 



It is well known to breeders of dogs 

 that yellows are of two very different 

 types. This holds true in the case of 

 pointers. One type is a bright, vivid 

 yellow with dark eyes and black nose. 

 The other type is duller and often lighter 

 yellow with pinkish-brown nose and light 

 eyes. The latter are considered inferior 

 in many breeds and are, therefore, seldom 



'In the table and test following, liver is used interchangeably with brown. 



