318 



The Journal of Heredit}' 



Because of the generality of this 

 practice one might expect that the 

 great majority of harlequins would be 

 heterozygous and that the result of 

 crossing two harlequins would be to 

 approximate a ratio of three harlequins 

 to one self colored. This as can be 

 seen from Table VI is exactly the result 

 obtained, and we may therefore con- 

 sider that it is extremely probable that 

 harlequin represents a form of spotting 

 depending upon a factor epistatic to 

 self colored. Furthermore, when harle- 

 quins are crossed with self blacks, the 

 small number of young obtained show 

 a ratio which is not significantly differ- 

 ent from a one to one ratio. This 

 supports the view that the harlequins 

 used for breeding are commonly hetero- 

 zygous. The matings of animals lack- 

 ing the harlequin spotting factor are 

 last to be considered. These have 

 given a total of 1,219 offspring. Of 

 these, five, or less than four-tenths of 

 one per cent, are harlequin, and the 

 remainder are self as expected. It is 

 extremely likely that these five excep- 

 tions are due to stud-book errors, for 

 they occur so rarely that it is hard to 

 believe that they are genetically signifi- 

 cant. 



The harlequin spotting factor appear? 

 to be not unlike the dominant spotting 

 observed by Barrows and Phillips in 

 cocker spaniels, although, of course, 

 the actual distribution of the spots- 

 differs in the two forms, those of the 

 Great Danes being far more irregular in 

 outline. 



(d) The Factor S for Self Color, and s for 

 "piebald" spotting 



The term "piebald spotting" is 

 perhaps a misnomer, for apparently the 

 only manifestation of this type of 

 spotting which exists in Great Danes is. 

 the occasional occurrence of animals 

 with a white chest spot or with white 

 feet, or with both. Such an animal is 

 shown in Fig. 12, No.l. Such forms 

 are not desired and are rigorously se- 

 lected against by fanciers. Inasmuch, 

 however, as their appearance depends 

 upon an hypostatic factor, the entire 

 elimination from any strain has proved 

 to be difficult, and they still crop out 

 at rare intervals. That they appear 

 less frequently than animals possessing 

 the other hypostatic factors already 

 considered is shown by Table VII. 

 Here matings of self x self animals 

 have given 1,214 offspring, of which 



Table VIII 



