THE SPECIFIC CHAllACTEliS OF BIRDS. 5129 
stance liable to alteration and misapprehension, in prefe- 
rence to the form and structure of that feather, qualities 
essential to its existence, permanent and positive, and not 
liable to misinterpretation ? 
In this point of view, the matter does not seem to admit 
of a doubt ; and it cannot but appear singular, that if the 
characters afforded by the forms of the feathers be in reali- 
ty such as they have been here represented, they should 
have been overlooked. They have not, however, been ab- 
solutely overlooked: as I have already mentioned, they 
have occasionally served to furnish an auxiliary character 
when they obtruded themselves, as it were, upon the view 
by some remarkable peculiarity, — chiefly, however, elonga- 
tion, and not form or structure. Ornithologists would seem 
to have looked upon tl?e plumage as one individual mass 
or aggregate ; and hence as capable of affording no other 
characters than those of dulness or glossiness of surface, a 
silky or harsh feel, and such like. But the moment it is 
considered as composed of very numerous parts, arranged 
into groups assuming a vast variety of characters, it cannot 
fail to excite attention, and direct the current of thought 
ijnto a new channel. 
By the opportunities afforded me in the course of my 
duty in the Museum, of observing the varieties of plumage 
in many hundreds of species, I have benefitted so far as to 
see, that a better mode of characterising species than any 
hitherto used, could, with some attention, be brought into 
a condition fit for application. Nor is it a crude idea that 
I have presumed to force upon the notice of the Society : 
it was first formed in the spring of last year, and since 
then I have fully convinced piyself of its practicability. 
Before applying tlie character, it would be necessary to 
form a sufficient nomenclature or terminology. This would 
not be an extremely difficult task ; and tlic nuinber of ncvr 
