GENERAL HABITS 203 



one can make a very exhaustive study of Birds 

 without soon coming to the conclusion that 

 colour plays a very important part, nay, many 

 parts, in their economy. No matter what de- 

 scription of haunt we select, we are pretty sure 

 to find within it birds of some kind presenting 

 in various ways protective modifications of 

 colour, not only for purposes of concealment 

 from enemies, but in some cases to enable 

 them better to steal upon their own prey. This 

 protective colouration often runs almost uni- 

 versally through entire groups of birds. In 

 the tropics, for instance, we have birds with the 

 prevailing tints of their plumage yellow or 

 green in many different families ; and we can 

 well understand of what vast service such hues 

 are amongst the evergreen foliage. In more 

 northern latitudes many of these gaudy-coloured 

 birds would be conspicuous enough, but here 

 in the virgin forests of the Equator their brilliant 

 hues and violently contrasted tints harmonise 

 completely with the vegetation. 



But the protective colours of forest birds do 

 not appeal so forcibly to the casual observer 

 as some of the hues that deck species living in 

 more open situations. Take desert birds, for 

 example. These birds are almost invariably 



