40 



INHERITANCE IN GUINEA-PIGS. 



male (6^140) produced 2 pink-and-red-eyed young. A pink-and-red- 

 eyed male mated with 2 dark-eyed females of race B, which were hetero- 

 zygous in albinism, produced 4 dark-eyed and 4 red-eyed young. 

 Another pink-and-red-eyed male (140) mated with a dark-eyed female 

 descended from d"1002 produced 1 pink-eyed young, in which red-eye 

 was undoubtedly recessive. Most of the foregoing matings are tabu- 

 lated in table 28. 



Table 28. — Character of young -produced 'in matings of pink-and-red-eyed descendants of c? 1002. 



Character of mate. 



Dark-eved 



Do 



Red-eyed 



Do 



Pink-eyed 



Albino 



Pink-and-red-eyed . 



Do 



Do 



Character of mating as 

 regards agouti. 



Agouti X agouti 



Agouti X non-agouti 



Agouti X agouti 



Agouti X non-agouti 



Do 



Do 



Agouti X agouti 



Agouti X non-agouti 



Non-agouti X non-agouti . . 



Total . 



Dark-eyed young. 



Golden 

 agouti. 



Black. 



Red-eyed young. 



Silver 

 agouti. 



2 

 4 



19 



Sepia. 



2 



2 



10 



21 



Character of mate. 



Dark-eyed 



Do 



Red-eyed 



Do 



Pink-eyed 



Albino 



Pink-and-red-eyed . 



Do 



Do 



Character of mating as 

 regards agouti. 



Agouti X agouti 



Agouti X non-agouti 



Agouti X agouti 



Agouti X non-agouti . . . . 



Do; 



.... Do 



Agouti X agouti 



Agouti X non-agouti 



Non-agouti X non-agouti . 



Total . 



Pink-eyed 

 young. 



Agouti. 



Non- 

 agouti. 



Pink-and-red- 

 eyed young. 



Agouti. 



4 

 1 



1 

 15 



21 



Non- 

 agouti. 



Albino 

 young. 



3 



1 



2 



18 



G 



2(?) 



1 

 2(?) 



30 



1+4 (?) 



Pink-and-red-eyed males mated with albinos of races free from pink- 

 eye produce red-eyed or albino young, but not pink-eyed young, since 

 pink-eye also is a recessive character and becomes visible only when 

 doubly represented in the zygote. 



It is clear, accordingly, that when pink-and-red-eyed animals are 

 mated with red-eyed animals (or albinos), young are produced which 

 are red-eyed, but in which pink-eye is recessive; and when the same 

 pink-and-red-eyed animals are mated with pink-eyed animals, young 

 are produced which are pink-eyed, but in which red-eye is recessive. 

 Hence thetwo characters, pink-eye and red-eye, are independent of each 

 other, though red-eye is the dominant allelomorph of albinism, with 

 which pink-eye is wholly unrelated. 



