162 A NATURALIST ON THE "CHALLENGER." 



is soluble in water, so that the birds are apt to wash their red 

 feathers white when in confinement. 



The colouring matter, " Turacin," as was discovered by 

 Prof. A. H. Church,* is distinguished by yielding a remarkable 

 absorption spectrum, and contains a considerable quantity of 

 copper. The bird is very common in the Knysna. and I was 

 told by sportsmen who had shot it, that in rainy weather it will 

 hardly fly, but crouches down under the bushes, and may some- 

 times be knocked down with a stick. 



A most extraordinary statement concerning these birds, to 

 the effect that the red colour, when washed out of the feathers, 

 becomes restored, is made by M. Jules Verreaux.f It seems 

 impossible to understand how this can happen, since there seems 

 no means by which the colouring matter can be conducted from 

 the body of the bird to the web of the feather. Such a result 

 seems only possible in Horn-bills, some of which, as is well 

 known, paint their feathers yellow by rubbing in a yellow 

 secretion discharged from glands under the wing. 



M. Yerreaux states that in rainy weather, just as I was 

 informed, the Turacous get their feathers wet through, and are, 

 in consequence, unable to fly, but crouch on the ground, instead 

 of resting on the tree-tops as usual. He caught several with the 

 hand, the colour came out on his hands from the wet feathers. 

 He washed the colour out of their wings with soap and water 

 till the feathers were almost white. The bright red colour 

 however, returned directly the feathers were dry, and this 

 occurred even when the same bird was washed twice in the 

 same day. 



The red colouring matter is scarcely at all soluble in pure 

 water, but the addition of the slightest trace of alkali to the 

 water enables it to extract the pigment from the feathers, and 

 yield a blood-red solution. 



For notes on P. N. Zealandine, see H. N. M. Ann. and Mag. Nat. 

 Hist., 1877, p. 85. 



* " Researches on Turacin," Phil. Trans., 1870, p. 627. 

 t M. Jules Verreaux, " Proc. Zool. Soc," 1871, p. 40. 



