132 THE NATURALIST'S GUIDE- 



observation, I have seen but three in the red plumage. 

 On the other hand, among more mature birds, I have, 

 out of perhaps forty specimens personally examined, found 

 but four or five in the gray! Mr. Allen informs me that 

 although such formerly was his experience, latterly he has 

 met with many more gray than red birds. By these evi- 

 dences I have become fully convinced that in the earlier 

 stages perhaps to the third year the coloration of 

 the plumage of Scops asio is exceedingly variable as a 

 species and somewhat individually, but in this last re- 

 spect it is more constant. The only doubt that now re- 

 mains is, Do birds of a certain age or period all assume 

 some particular plumage as a final one 1 I am now inclined 

 to think they do. Perhaps the final stage is gray ; but 

 this, as I said before, yet remains to be proven. It seems 

 to be an imperative law of nature for birds, no matter 

 how variable and inconstant their plumages in earlier 

 stages may have been, at some age or period to as- 

 sume a final one, with the specific characters variable in 

 a comparatively small degree, as heretofore pointed out. 



This inconstancy of plumage is also illustrated in the 

 young of the Cedar-Bird (Ampelis cedrorum) ; mature speci- 

 mens of this species always have the peculiar, sealing-wax- 

 like, horny expansions of the shaft of the feathers on the 

 tips of the secondaries, and sometimes on the tips of the 

 tail-feathers. In the younger stages many are destitute 

 of them. I have, however, detected it upon the second- 

 aries, and even upon the tails, of birds in the nesting plu- 

 mage. 



With these facts to guide us, we can but adopt the 

 above hypothesis relative to the final assumption of some 

 particular plumage by Scops asio, until it has been proven 

 that this is an exception to the governing and heretofore 

 unchanging law of nature. 



This bird sees as well in the daytime as in the night 



