Abstract
The authors compared the first phalanx of the second wing-finger of 93 species belong to 9 order (Gaviiformes – 2 species, Podicipediformes – 4 species, Pelecaniformes – 4 species, Ardeiformes – 12 species, Anseriformes – 27 species, Gruiformes – 4 species, Ralliformes – 6 species, Charadriiformes – 25 species and Galliformes – 9 species). The importance of studying this bone lies in the fact that, although it has diagnosable characteristics, it was practically neglected by osteologists and paleontologists. Thus, fossil materials can be identified through them, as well as those from owl pellets. The comparison was made possible by the comparative avian skeleton collection of the Hungarian Natural History Museum. The text is supplemented by 10 figures and 1 table.