BIRDS OF NORTH AND MIDDLE AMERICA. 3 
habits, a plain coloration characterizes the entire group, not a 
single species possessing a brilliant plumage, while the majority 
are among the dullest colored of birds. They are mostly forest 
birds, though the Pteroptochide and some of the Furnariide inhabit 
bushy tracts or even more open places. The Pteroptochide, 
Conopophagidez, and Formicariide are chiefly terrestrial, but the 
Dendrocolaptide and many of the Furnariide glean their food 
from the trunks of forest trees, in the manner of Woodpeckers and 
Creepers. 
In Dr. Sclater’s catalogue of the Tracheophonez,* 559 species are 
recognized; but since this number represents only those that were 
autoptically known to the author it may safely be assumed that the 
actual number of recognizable forms, including subspecies, is not far 
from 800.° 
KEY TO THE FAMILIES OF TRACHEOPHONS. 
a. Only one pair of tracheo-bronchial muscles; metasternum 4-notched, or else (in 
Formicariide) tensor patagii brevis tendon normally passerine and nares holo- 
rhinal; tarsal envelope not exaspidean (endaspidean, taxaspidean, or holas- 
pidean). 
b. Metasternum 4-notched; tensor patagii brevis tendon quasi-picarian. ¢ 
c. Interorbital septum perforate; postorbital process small, placed low down on 
side of skull; maxillo-palatines long and slender, curved backward; vomer 
short, with long limbs; intrinsic muscles present; sterno-trachealis not attached 
to processus vocales; palate egithognathous (oscinine); mesorhinium com- 
pressed and arched or else expanded into a flattened oval shield; nostrils 
conspicuously operculate; tarsal envelope taxaspidean or holaspidean. 
Pteroptochidee (p. 4) 
@Catalogue | of the | Passeriformes, | or | Perching Birds | in the | Collection | of 
the | British Museum. | — | Tracheophone, | or the Families | Dendrocolaptide, | 
Formicariide, | Conopophagide, and Pteroptochide. | By | Philip Lutley Sclater. | 
London: | Printed by order of the Trustees. | 1890.—8vo, pp. xviii X 372, pl. xx. 
(Volume XV of the “Catalogue of the Birds in the British Museum.’’) 
b In Sharpe’s Hand List of the Genera and Species of Birds (vol. iii, 1901, pp. 4-87) 
the number of forms recognized as belonging to the American Families alone is 799, 
as follows: 
Species. Genera. 
Pteroptochide....-......2. 2.22.0. cece eee eee eee 31 8 
Conopophagideé s....1cccsecase eves ve selsigactesen ss esos cities 16 2 
Forimicariidse 2 russes es as recanien oetuisie’s sia crane aes 347-388 
Purnarlidee.iccvscesecetes x esis eeceeatiodewe ys ues exeeeaee 278 37 
Dendrocolaptidae: 0... cee sis es cada eset web eres nes 127) («4 
Total. cs caesaaicsitiianeees os aaa basa eden cs nema gasiae 799 99 
The enumeration of species, however, includes subspecies, which are not distin- 
guished typographically or otherwise in the list. The Furnariide and Dendrocolap- 
tide are treated as one family, as in the British Museum catalogue. 
¢ The returning portion concealed by the muscular fibers at the origin of the extensor 
metacarpi muscle. (See Stejneger, Standard Nat. Hist., Birds, p. 476.) 
