NATURAL HISTORY NOTES 71 



diseases to which the race are subject 

 in this country being largely due to 

 departure from natural conditions in 

 their state of life and surroundings, 

 any mention of their cause and cure will 

 find more suitable place among the notes 

 on the rearing-field in a later chapter. 



Varieties in plumage among pheasants 

 are not uncommon ; the stone-coloured 

 edition of the normal cock, commonly 

 known as the ' Bohemian ' pheasant — and 

 so persistent and true to type that earlier 

 naturalists were more confident in con- 

 sidering him a normal race or species 

 than the ring-necked bird — is well known 

 to all, if not in the flesh then at least as 

 an ornament in the hall or gun-room of 

 any country house. Pied and white birds 

 are a common by-product of the rearing- 

 field, although almost unknown among 

 birds unaffected by the influences of 

 aviary or rearing-field. Natural mating 

 of white with normal coloured birds, 

 results in offspring with little tendency 

 to albinism, though probably by careful 



