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The Journal of Heredity 



pigmentation of the fawn. The blue 

 is a true dilute type, apparently directly 

 analogous to the maltese cat and the 

 "dilute black" mouse or rabbit. 



Brindles vary considerably in depth 

 of color. They may have a rich, 

 golden ground color or a duller and 

 darker brown. The pattern which ap- 

 pears on this ground color is an ir- 

 regular streaking with black. It is 

 variously described as brindled, 

 streaked, striped, or tigered. The rel- 

 ative amount of black and yellowish- 

 brown pigment in the coat varies con- 

 siderably, some brindles being almost 

 entirely fawn with a trace of black, 

 and others being predominantly, if not 

 entirely, black, in appearance. Some 

 evidence that brindles may rarely be 

 entirely black in appearance or, at the 

 other extreme, fawn, will be presented 

 when the detailed color crosses are 

 considered. 



Dilute brindles have a dull, silvery 

 type of coloration affecting both the 

 ground pigment and the dark striping 

 and giving an appearance easily dis- 

 tinguishable from the light but in- 

 tensely pigmented brindles. The dif- 

 ference is qualitatively almost exactly 

 that recognized in other mammals and 

 described by one of the writers in the 

 case of yellow mice (Little, 1911). 



Spotted forais are of two sorts, 

 harlequins already described, and dogs 

 on which small white spots occur on 

 the chests or feet. (Fig. 12, No. 1.) 

 Harlequin is a pattern producing, on the 

 one hand, a pure white animal with a 

 dark nose, and on the other hand an 

 animal with a very small amount of 

 white. Individuals of the latter sort 

 might possibly be confused with animals 

 possessing spotting of the second (non- 

 harlequin) type. Animals with the 

 second type of spotting are not con- 

 sidered desirable specimens, and are in 

 Great Danes, as in other breeds, vigor- 

 ously selected against. The effects of 

 this upon their occurrence and descrip- 

 tion will be considered later. 



(c) Review of Previous Literature. — 

 One of the writers (Little 1914) has used 

 the American Kennel Club Stud Books 

 for the purposes of studying color in- 



heritance in pointers and has reportep 

 the existence of certain alternative color 

 types referable to Mendelizing factors. 

 One of these, the factor for black pig- 

 ment, the hypostatic form of which pro- 

 duces brown pigment, had been observed 

 previously by Lang, 1910, in a single 

 cross which he made. This mutation 

 from large B to small b does not appear 

 to have occurred in Great Danes in so 

 far as the records studied are con- 

 cerned. One dog was described as 

 "liver" in color, but inasmuch as blue 

 commonly approaches "liver" in ap- 

 pearance and, further, inasmuch as this 

 dog occurred in a mating where blues 

 would be expected, the dog in question 

 has been classed as blue. The second 

 factor to be recognized in pointers is 

 the factor E for the extension of black 

 and brown pigment in the coat. In 

 the hypostatic foi-m of this factor the 

 colored portions of the coat are orange 

 or lemon-yellow. Whether the yellow 

 of pointers is identical with, or com- 

 parable to, the fawn type of Great 

 Danes is doubtful. It represents a 

 distinctly yellow type in which there 

 is no marked darkening of the muzzle 

 or the extremities such as one finds in 

 fawn Great Danes. Until further care- 

 ful experimentation is made, therefore, 

 we shall have to recognize four distinct 

 and possibly genetically different types 

 of red-yellow coat pigmentation in 

 dogs: First, the orange or lemon- 

 yellow of pointers and English setters; 

 second, the brownish-yellow of most 

 "red" dachsunds, and possibly of Irish 

 terriers; third, the dark, muzzled fawn 

 of bulldogs, greyhounds, and Great 

 Danes ; and finally, the almost mahogany 

 red of Irish setters. The genetic re- 

 lationships of these four types would 

 make a most interesting study. 



In 1915, Barrows and Phillips found 

 that the B and E factors were both 

 present in cocker spaniels, and in 

 addition discovered indications of a 

 dilution factor producing dilute black 

 or blue individuals and also, in the 

 yellow series, cream or white. On 

 page 393 they state that dilute reds 

 are cream in color. Whether, however, 

 dilute reds might not also be dull 



