INTRODUCTORY REMARKS. 
The classification of birds, both, in reference to the higher groups and to their subdivisons, is 
a subject which has engaged the attention of a large number of naturalists, although until 
within a comparatively short time there has not been any very great difference in the systems 
adopted by the leading writers on general ornithology. The more commonly received basis has 
been the character of the bill and the shape and general structure of the feet, as expressed in 
the terms Raptores, Insessores, Scansores, Basores, Cursores, Grallatores, and Natatores of most 
authors ; the Insessores again divided into Fissirostres, Tenuirostres, Dentirostres, and Coniros- 
tres, and, according to some systems, including, also, the Scansores as a subdivision, instead of 
that group being of higher independent rank. 
Within a few years, however, a great change has taken place in the methods of ornithological 
classification, and most continental authorities have abandoned the old arrangement of the non- 
rapacious land birds, as based on the shape and character of the bill, and substituted a much 
more natural system. The principal agents in this reform have been Nitzsch, 1 Andreas Wagner, 
Sundevall, 2 Keyserling and Blasius, 3 J. Miiller, 4 Cabanis, 5 Bonaparte/ Reichenbach, 1 Hart- 
laub, Burmeister, 8 and several other systematic writers, all contributing more or less to the 
final result. The most important step was the discovery announced by Miiller in reference 
to the presence or absence of certain peculiar vocal muscles, which proved the key-note to 
an entirely new arrangement. In addition to this there has heen latterly taken into 
account the number of primary quills, (or quills on the first joint of the wing,) whether ten or 
nine, and if ten whether the first be about as long as the second, about half as long, or very 
rudimentary ; also the character of the feet, whether the toes be three anterior and one pos- 
terior, or two anterior and two posterior, (and if so, whether the inner or the outer anterior 
toe he reversible,) or four more or less anterior. Particular reference is also made to the 
peculiarities of the scales on the legs, the position of the hind toe in relation to the plane of 
the others, the extent of feathering on the legs, the amount of webbing between the toes, the 
number of tail feathers, &c. 
In the following report I have followed very closely the outlines given by Cabanis, in the 
" Ornithologische Notizen," already quoted, although obliged, in most cases, to construct the 
1 System der Pterylographie, verfasst von Herm. Burmeister. Halle, 1840. 
2 Konglig. Vetensk. Akad. Handlingar, 1835 and 1843. Stockholm. 
3 Wirbelthiere Europas. Braunschweig, 1842. 
4 Ueber die bisher unbekannten typische Verschiedenheiten der Stimmorgane der Passerinen. Abhandl. K. Akademie 
der Wissenschaften zu Berlin, for 1845, 321. Berlin, 1847. 
5 Ornithologische Notizen, I, II, in Wiegmann's Archiv fur Naturgeschichte, 1847. 
6 Conspectus generum avium, Leyden, 1850 and 1857, and various papers since 1850, in Comptes Kendus, and elsewhere. 
7 Avium systema naturale, and Handbuch der speciellen Ornithologie. 
8 Systematische Uebersicht der Thiere Brasiliens ; Dritter Thail. (Vdgel.) Berlin, 1856. 
lb 
