-1-04' C. J. Suiidevall on the IVhigs 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 tbey can only be distinguished by their dimi- 

 nished size, and they always show a clear ti'ansition 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, Gallinee, and Water-birds. 

 They miist simply be called innermost (internse) or divergent 

 (diffbrmes), 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 Railing, FringiUa, 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 Motacilln, 

 Anthus, and Alauda, which in this respect, and by many 

 other resemblances, show great analogy with the Tringace?e. 

 In number the cubital quill-feathers vary very consider- 

 ably, namely between 6 (in Trochilus) and 36-40 (in Dio- 

 medea exulans) . I append a table [Appendix II.] for the more 

 accurate elucidation of these conditions, showing that the 

 number is in general greatest in Water-birds, some of the 

 Waders {Ardea, Ciconice) and Raptorial birds (Vulturinaj) ; 

 that the average number in the other Raptorial birds, Gal- 

 ling, 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. 



