No. 588] INHERITANCE OF SPOTTING IN MICE 739 



we should have 2 spotted, 1 black-eyed white and 1 self. 

 The results are as follows : 



Whether the excess of "self" animals is significant is, 

 of course, a question to be borne in mind but it is ex- 

 tremely doubtful whether it is due to anything more than 

 a chance deviation. 



Type "B" animals have, upon mating with "piebald" 

 individuals, given very close to the expected ratio of 1 

 type "B" to 1 "piebald." The exact numbers are 

 82 : 78 ; expected ratio 80 : 80. 



Is Black-eyed White in Mice an Allelomokph of 

 Albinism ! 



The experiments of Castle and Wright have shown that 

 a dark red-eyed variety of guinea-pig exists which is an 

 allelomorph of dilute pigmentation and of albinism. This 

 possibility in the case of mice is eliminated by crossing 

 black-eyed white with albino, when on the supposition 

 that the condition found in guinea-pigs holds true in mice 

 all the young should be either black-eyed white, albino or 

 dilute pigmented. Actually there were obtained from a 

 single mating of this sort five young, all intensely pig- 

 mented, two blacks and three browns ; thereby eliminating 

 the possibility that black-eyed white, in mice, is an 

 allelomorph in the albino series. 



Conclusions 



The fact that black-eyed white spotting in mice ap- 

 pears to be due to a factor independent of and supple- 

 mentary to the factor for "piebald" spotting leads to 

 interesting speculation as to the nature of spotting and 



