Magpie Colouring 
tail black. This occurs in the following birds 
belonging to the most diverse groups :— 
The Magpie. 
The Magpie Tanager (Czssopzs leveriana). 
The Magpie Robin (Copsychus saularts), cock 
only ; in the hen the black is replaced by brownish 
grey. 
The Pied Honeyeater (EZxtomophila picata). 
The Chaplain Crow (white-bodied form of the 
hoodie crow). 
The New Ireland Swallow Shrike (Avtamus 
2nSignts). 
The Magpie Goose (Anseranas melanoleucus). 
Combinations of this kind, in which the black 
is replaced by brown or grey, are excessively rare. 
On the other hand, we see in several birds the 
combination in which the white is replaced by 
yellow :— 
The Common Troupial (/cterus vulgaris). 
The Black-headed Oriole (Ovzolus melano 
cephalus). 
The Black-and-yellow Grosbeak, male only. 
What we may call imperfect magpie coloura- 
tion, z.e¢. where the head becomes white, occurs 
in several species of birds. The head of a black 
species sometimes becomes white as a mutation ; 
in the domestic Muscovy duck, for example, an 
individual is sometimes produced having a white 
head, although the black of the remainder of the 
plumage remains unchanged. 
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