294 The Bird 
climate, the birds, and in fact all of the animals, are of 
a much lighter hue than those living in an atmosphere 
of great humidity, where moisture does not readily evapo- 
Fig. 234.—Male Scarlet Tanagers, showing moult from the scarlet summer dress, 
(a), through the parti—coloured garb (b), into the green winter plumage (c). 
rate. Insucha place birds tend to be very dark-coloured. 
In the case of captive birds, I have seen White-throated 
Sparrows and Wood Thrushes become almost like black- 
