114 On Heterochromia Iridis in Man and Animals 



bull eye, and only the blues, and blues a.nd whites show irregular iris 

 pigmentation. 



One of the blue and white birds of the F^ generation is especially 

 interesting, having a full orange red eye on the right side and a " bull " 

 eye on the left. Plate VII, figs. 1 and 2. 



On careful examination with a lens however the red anterior 

 pigment in the right eye is found to be partly wanting in a segment 

 of the lower half of the iris downwards and a little forwards from the 

 pupil, leaving the underlying brown or " bull " ground colour exposed 

 in this situation. 



This individual bird thus shows a duplex pattern with coloboma of 

 the colour pattern in the right eye and the bull eye which corresponds 

 to the human simplex type in the left eye. This bird also showed 

 some irregular white patches on the head indicating further irregular 

 pattern of feather colour. 



The details of the breeding of these birds are as follows : 



White Fantail x 

 Bull Eyes I 



Black Tumbler 

 Pink Eyes 



Black and White 



Pink Eyes 



44 



Brown, Blue and White 

 Pink Eyes 

 26 



Almond 



1 

 Pink 



Almond 

 and White 



Blue 



Blue and 

 White 



Black and 

 White 



1 

 Pink 



4 

 Pink 



Brown, Blue 



and White 



5 



Pink 



White 



2 



Bull 



Irregular iris pigmentation 



In this case then the heterochromia and the irregular duplex 

 pattern in the right eye have appeared in the F^ generation during 

 the repeated interbreeding of the black and white, and brown, blue and 

 white heterozygous offspring of a bull eyed white fantail, and a pink 

 eyed black tumbler. 



