C. J. Bond 137 



Experiment 3. 



A Hybrid Tumbler Fantail Pigeon was bred of the following Genetic 

 composition : 



e White Fantail x ? Black Tumbler 



1 



Black and White x Brown, Blue and White 



do. s I do. ? 



I 1 1 1 1 1 



III 11 



Brown Black Black and White x Brown, Blue and White White 



do. s I do. ? 



III I III 



Blue Almond Blue and Almond and Black and Brown, Blue White 

 White White White and White 



I I 



Blue and White x Almond and White 



i I ? 

 J- ^ 



I I 1 



6 Blue and White 3 Blues 1 White (N.B. 2 died soon after 



hatching) 



Blue and White x Same Hen 

 S 

 Subcapsular Orchectomy, 

 Sept. 17, 1908 



I 1 1 — ' 1 1 



III I I 



Blue 11 Blue and White 9 Almond 2 Almond and White 5 White 7 



N.B. Three died soon after hatching. 



From the above table we see that the Blue and White Cock mated 

 with an Almond and White sister produced, before castration, 10 young 

 pigeons of which number one only was white. After castration and 

 regeneration of the testes the same pair produced 34 young pigeons of 

 which seven were white. 



It is interesting to notice that in the smaller number of young 

 hatched before castration, the proportion of Recessive White to the 

 rest was 1 in 10, while after castration and regeneration of the testes 

 the proportion of Recessive White to the rest (in the larger numbers) 

 was nearly 1 in 5. 



Although in the case of the fowl the male contribution to the 

 zygotes hatched before and after regeneration of the testes were alike 

 in character, as judged by the appearance of the chickens, this result 

 may have been due to the fact that only one kind of gametes was being 

 formed by the testes of the particular bird operated on, and so the 



