172 Proceedings of the Royal Physical Society. 
chief object aimed at was to record the external characteristics 
as they appeared in the living birds, and the paper was 
addressed to those who, like myself, were engaged in zoologi- 
cal art-work. For such a purpose it was not at all necessary 
to enter into any detail respecting the structural characters of 
the wings, or even to discuss the more important matter of 
the insertion of the feathers. Since that paper was read, the 
relationship of each group of feathers to the bony framework 
of the wing has received a considerable amount of attention 
from Dr Sclater, Dr Gadow, Professor Flower, Mr Wray, 
Mr Pycraft, and others; and I have myself by no means 
neglected the subject. The main features at present known 
may, therefore, advantageously be set forth here. 
Attention will be confined in this paper exclusively to the 
feathers that appear upon the outer face of a wing, as being 
those that are subject to the more interesting sets of variations. 
Regarded in connection with their insertion upon the fore- 
limb of a bird, the feathers may be primarily grouped into 
(1) those seated upon any part of the humerus; which will 
be herein referred to as the Postcubitals or Humerals. (2) 
Those originating upon any part of the forearm, or of the 
integuments connected therewith; these will be termed the 
Cubitals. (3) The feathers seated-upon any part of the wing 
beyond the carpal end of the forearm, including those seated 
upon the carpus proper, as well as those originating upon the 
metacarpo-digital region; for these, collectively, the name 
Antecubitals will be used in this paper. 
The Humerals present some interesting features, but it is 
not proposed to study these now. The Cubitals naturally 
group themselves into four sets, to which, for convenience of 
description, it is customary to add a fifth set. These are, 
counting from the flight feathers towards the front edge of 
the wing, (1) the Remiges, which call for no special remark at 
present; (2) the Major Coverts. The base of each remex is 
attached to the under side of the ulnar, and the Major 
Coverts, which theoretically correspond in number to the 
Remiges, form a single row, which is based nearly on the 
same level as their respective primaries, but a little on their 
humeral side. Their shafts are set somewhat obliquely, so 
