416 C. J. Sundevall on the Wings of Birds. 
between the roots of the remiges and greater covert-feathers, 
or within the muscular layer, close upon its hinder limit. 
(The latter in the Oscines, e. g. Parus .) They are most 
visible in the Oscines, in consequence of the absence of 
the next series, and are quite short, soft, and usually distin¬ 
guished by a peculiar colour-marking, e. g. white at the apex 
in many, so that they form a transverse band upon the wing. 
(A transverse band upon the wing is almost still more fre¬ 
quently produced by the apices of the greater covert-feathers, 
which, in the Song-birds, are often white, yellow, or of paler 
colour). 
These feathers seem to have been but little observed. Ac¬ 
cording to the definition in Illiger^s 1 Terminologie/ they 
constitute his “ptila” which are said to lie immediately within 
the pteromata; but the want of any special name for all the 
following smaller feathers seems to show that Illiger included 
them also under the name of ptila. In the Song-birds, in 
which they alone are reversed , they may receive this name 
(perversa ) ; but it seems to me to be safest to employ the 
denomination above given, which at any rate is correct. If 
we had not accustomed ourselves to an entirely different signi¬ 
fication of the names primaries and secundaria , these terms 
would undoubtedly have been best of all adapted for these 
two series, the first and second coverts. 
3. The Tectrices minores cubiti vel manus (smaller wing- 
coverts, figs. 2, 3 b) form several (2-5) series inserted in 
the skin upon the bones and muscles of the arm or hand 
itself. In form they do not differ at all, or but slightly, from 
the feathers of the body, and in position they agree with the 
next preceding series, inasmuch as their margins cover each 
other in a contrary way to those of the remiges. But they 
lie similarly reversed also in those birds in which those of 
the second series are not reversed ( Coracias, Cuculus , &c.). 
In the Song-birds these feathers should properly form 
three series on the cubitus, but they show the remarkable 
peculiarity that they are never fully developed. Only in the 
young in their first plumage, and in the winter plumage, a 
few of them, but never all, occur in the form of down, or of 
