404 
C. J. Sundevall on the Wings of Birds. 
much diminished in size, and have frequently a different 
colour and structure from the rest. They are, in this case, 
softer, more pointed, &c., and both in form and colour 
resemble the feathers of the back. These have been called 
tertiary wing-feathers, which, however, can hardly be con¬ 
sidered right, for they are usually seated upon the cubitus, 
like the other cubital quill-feathers, from which in a great 
many birds they can only be distinguished by their dimi¬ 
nished size, and they always show a clear transition to them 
in form and position. Nevertheless the series is continued 
beyond the joint, so that some of the last are seated upon the 
humerus in most Raptorial birds, Gallinse, and Water-birds. 
They must simply be called innermost (internee) or divergent 
(difformes), because they differ in form and colour from the 
rest. The latter is, indeed, always the case to some extent 
with a couple of the innermost quill-feathers; but a con¬ 
siderable difference is observed only in some few genera of 
diverse orders ( e.g . in some Anates ), strikingly in all the 
Tringacese and Charadriacese and in Grus, less signally in 
some of the Rallince, Fringilla, and Emheriza, Linn.; in a 
still less degree in the Sylvia and many of their allies (but 
scarcely perceptibly in the Turdi ), and especially in Motacilla , 
Anthus, and Alauda , which in this respect, and by many 
other resemblances, show great analogy with the Tringacese. 
In number the cubital quill-feathers vary very consider¬ 
ably, namely between 6 (in Trochilus) and 36-40 (in Dio- 
medea eoculans ). I append a table [Appendix II.] for the more 
accurate elucidation of these conditions, showing that the 
number is in general greatest in Watet-birds, some of the 
Waders (. Ardece , Ciconia ) and Raptorial birds (Vulturinse) ; 
that the average number in the other Raptorial birds, Gal- 
linse, and Waders is 15-16, which also occurs in many 
Water-birds; that most of the Coccyges have 10-13, but 
that in these, as in all the fore-named orders, the number 
varies, even in species of the same genus. Only the Song-birds 
have a nearly constant number—nine, which is the smallest 
number of general occurrence. Only Trochilus and Cypselus 
(among the Coccyges) have still fewer. 
