403 C. J. Sundevall on the Wings of Birds. 



In the Song-birds^ without exception, the first feather is 

 abbreviated. In a somewhat higher degree this takes place 

 in two different ways. In a part of them some of the 

 feathers (the anterior) are gradually shortened, by which 

 means the wing becomes short and rounded, and the first 

 feather somewhat shorter than the second (e. g. Gurrulus, 

 Regulus, TimaIi(B, Mijiothera) ; these birds usually fly badly, 

 are seen much upon the ground, and do not fly far. In 

 others the feathers of the first finger-joints (uos. 2-V) are 

 moderately long and exceed the others ; but when this 

 occurs among the Song-birds it is usual for the first feather to 

 be so reduced in size that it either remains as a small rudi- 

 ment or entirely disappears; and in this latter case there are 

 only nine primaries (as in fig. 8). This reduction of the 

 first feather is peculiar to the Song-birds, but among them 

 it is quite usual. We may, indeed, estimate that one fourth 

 of the known species are destitute of the first quill-feather, 

 one fourth have it rudimentary, one fourth have short 

 rounded wings with ten primaries, and the remaining fourth 

 have tolerably long wings, but with the first feather shorter 

 than those that follow (e. g. Corvus, exotic MuscicapcB, 

 &c.) . It would appear therefore as if in the Song-birds there 

 was a compensation between the development of the feathers 

 of the first and second joints of the finger, so that the increase 

 of the latter brought with it a diminution of the first feather. 



The first feather is deficient especially in many American 

 species ; namely, the American Sylvia and their allies, in the 

 Tanagra, Evphone, Hirundo, and all American Sturninae and 

 Passeres. In the Old Continent it is deficient in Anthus, 

 Motacilla, Hirundo, and in about one half of the Passeres. 



A rudimentary first wing-feather occurs in America almost 

 solely in the Turdi ; but in the Old World in the Turdi and 

 Sylvia and many of their allies, in the Lanii (pars), Gracu- 

 linae, Cinnyriufe, Alaudse, and the Ploceini among the 

 Passeres. 



The decrease in size of the outer quill -featliers, or their 

 disappearance, is generally shown more in the fully de- 

 veloped dress and in the males than in the w^inter garb or 



