PARAGRAPHS ON PLUMAGE. 255 



larly soft and fluffy plumage, well adapted to their 

 nocturnal habits, when these birds have to pounce 

 softly and silently on their prey at a time when 

 the least sound is heard far and wide. Yet the 

 Goatsuckers also exhibit this peculiarity, which 

 has probably been inherited from the common 

 ancestor of the Owls and the Nightjars. The 

 plumage of some birds is remarkably loose and 

 pervious, as in many of the Passeres ; hard and 

 compact, as in the Pigeons ; dense and waterproof, 

 as in the Ducks and sea-birds. Birds which in- 

 habit cold climates are well provided with a warm 

 covering, two of the most remarkable instances 

 being the Siberian Jay and the Lapp Titmouse, 

 which are constant residents in forests where the 

 temperature in winter is so low that few creatures 

 can exist. 



The whole subject of birds' plumage has been 

 little studied or investigated, yet it presents an 

 unusually rich field for careful observation and 

 patient research. I cannot but think that the 

 investigation, if properly made, will throw much 

 light on the past history of birds, and clear up 

 many points in their affinities which are still 

 buried in clouds of obscurity. I offer these few 

 remarks merely as hints of encouragement for the 

 reader to take up the study of this branch of 

 ornithology, rather than any serious discussion of 

 the question, which is too complicated and far too 

 important to be dealt with in a few cursory pages. 



