COLOURS ORT TOU COU 
touracous come nearest to the cuckoos in systematic 
position. But it is clear that, after all, they are a 
somewhat isolated race. The principal fact of interest 
about them is the red colouring matter of the wing 
feathers. In considering the peacock, it is pointed out 
that colours in birds’ feathers may or may not depend 
upon the presence in the feather of a pigment of that 
particular hue. In the peacock the bright metallic 
tints are the product of the feather structure and of a 
blackish pigment below. In the touracou, on the con- 
trary, the red feathers contain a red pigment, which 
can be dissolved out, and which shows in solution the 
same fine colour that it shows when embedded in the 
substance of the feathers. Some characteristics of this 
pigment have given rise to what must be regarded as 
rather a legendary history. It has been noticed that 
in wet weather these birds confine themselves to the 
densest shades of their native thickets, a proceeding 
on their part which is not at all unusual fora bird. But 
a special reason for this was alleged in the case of the 
touracou. The red pigment was held to be dissolved 
out by the warm tropical rain, leaving the feather 
blanched. It was furthermore added, with perhaps an 
eye to paradox and effect, that when the bird was shot 
and happened to fall into water, it dyed the stream 
red, not with its own blood, but with the dissolved 
crimson pigment. The actual facts upon which these 
statements have been based is that the colour can be 
removed from the feathers by steeping them in alkalis. 
And furthermore that ordinary tap water, which is as a 
rule slightly alkaline, will be tinged to a perceptible 
extent after a feather has been steeped in it, particularly 
if the water be warm. It is, however, doubtful whether 
a touracou is bleached by exposure to a tropical or 
any downpour. The name turacin has been applied 
to this pigment, and it is characterized, a somewhat 
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