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 Pteroptochidæ and some of the Furnariidæ inhabit bushy tracts or even more open places. The Pteroptochidæ, Conopophagidæ, and Formicariidæ are chiefly terrestrial, but the Dendrocolaptidæ and many of the Furnariidæ glean their food from the trunks of forest trees, in the manner of Woodpeckers and Creepers.
In Dr. Sclater's catalogue of the Tracheophonse,[1] 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.[2]
KEY TO THE FAMILIES OF TRACHEOPHONÆ.
a. Only one pair of tracheo-bronchial muscles; metasternum 4-notched, or else (in Formicariidæ) tensor patagii brevis tendon normally passerine and nares holorhinal; tarsal envelope not exaspidean (endaspidean, taxaspidean, or holaspidean).
- b. Metasternum 4-notched; tensor patagii brevis tendon quasi-picarian.[3]
- 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 ægithognathous (oscinine); mesorhinium compressed and arched or else expanded into a flattened oval shield; nostrils conspicuously operculate; tarsal envelope taxaspidean or holaspidean.
- ↑ Catalogue | of the | Passeriformes, | or | Perching Birds | in the | Collection | of the | British Museum. | — | Tracheophonæ, | or the Families | Dendrocolaptidæ, | Formicariidæ, | Conopophagidæ, and Pteroptochidæ. | By | Philip Lutley Sclater. | London: | Printed by order of the Trustees. | 1890. — 8vo, pp. xviii × 372, pl. xx. (Volume XV of the "Catalogue of the Birds in the British Museum.")
- ↑ 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. Pteroptochidæ 31 8 Conopophagidæ 16 2 Formicariidæ 347 38 Furnariidæ 278 37 Dendrocolaptidæ 127 14 Total 799 99 The enumeration of species, however, includes subspecies, which are not distinguished typographically or otherwise in the list. The Furnariidæ and Dendrocolaptidæ 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.)
