The Woodheiver Family. 249 



brown hue being of a shade that assimilates very 

 closely to the surroundings. There are pale 

 yellowish browns, lined and mottled, in species 

 living amidst a sere, scanty vegetation ; earthy 

 browns, in those frequenting open sterile or stony 

 places ; while the species that creep on trees in 

 forests are dark brown in colour, and in many cases 

 the feathers are mottled in such a manner as to 

 make them curiously resemble the bark of a tree. 

 The genera Lochmias and Sclerurus are the darkest, 

 the plumage in these birds being nearly or quite 

 black, washed or tinged with rhubarb yellow. Their 

 black plumage would render them conspicuous in 

 the sunshine, but they pass their lives in dense 

 tropical forests, where the sun at noon sheds only 

 a gloomy twilight. 



If " colour is ever tending to increase and to 

 appear where it is absent," as Dr. Wallace believes, 

 then we ought to find it varying in the direction of 

 greater brightness in some species in a family so 

 numerous and variable as the Dendrocolaptida?, 

 however feeble and in need of a protective colour- 

 ing these birds may be in a majority of cases. And 

 this in effect we do find. In many of the dark- 

 plumaged species that live in perpetual shade some 

 parts are a very bright chestnut ; while in a few 

 that live in such close concealment as to be almost 

 independent of protective colouring, the lower 

 plumage has become pure white. A large number 

 of species have a bright or nearly bright gular spot. 

 This is most remarkable in Synallaxis phryganophila, 

 the chin being sulphur-yellow, beneath which is a 

 spot of velvet-black, and on either side a white 



