C. J. Sundevall on the Wint/s of Birds. 3D3 



the year 1835. Nevertheless I had not then grasped the 

 whole iniportanee of these characters as external distinctions 

 between the birds which do or do not possess singing-muscles 

 on the inferior larynx, for I still believed that 1 found excep- 

 tions in the genera Picus, Upvpa, and Menura. Later inves- 

 tigations have shown that these genera do not deviate from the 

 general rule, and that the presence or absence of the so-called 

 singing-apparatus is indicated by two dissimilar structures of 

 the wings. After the year 1834 other studies occupied my 

 time, so that this subject did not again come under examination 

 until the report of the statement of Keyserling and Blasius 

 of the (in their opinion) first positive external characters for 

 Song-birds, caused the subject to be again taken up in the 

 zoological ''Arsberattelse^' of the Academy of Sciences, printed 

 in 184?1 (p. 126). As I soon afterwards, in the same year, 

 undertook a journey into foreign countries, I communicated 

 the matter to several individual zoologists, and also to the 

 Meeting of Naturalists at Brunswick. The Transactions of 

 that meeting, however, contain no more than had already 

 been made known in print in 1835, A somewhat more 

 detailed exposition of the subject was first made before 

 the Meeting of Scandinavian Naturalists in Stockholm in 

 1842, and this is printed in the Transactions of that 

 Meeting (p. 685) . In the present paper 1 venture to give 

 a description of the bird's wing somewhat more in detail. 



First. Chapter. 



General Revieiv. 

 The bird's wing consists of the following parts : — 

 1. The anterior extremity, namely : — Humerus (upper arm, 

 PI. X, figs. 1, 2, &c., a), cubitus (forearm, b), and hand 

 (manus, c), which again is composed of the carpus (wrist, v), 

 metacarpus (middle hand, c), first phalange {y) and the 

 second {z) , with the pollex (thumb, d) . 



Although it is not my intention here to describe anything 

 but the exterior and its coverings, it may nevertheless be 

 stated in passing that the two l)ones of the forearm, the 

 ulna (fig. 1,^) and the radius {h), are always separate i)i birds. 



