BIRDS OF NORTH AND MIDDLE AMERICA. 683 
aa. Tarsus shorter than first digit; head with a crest or with mystacial or superciliary 
plumes, flanks with a patch of downy or silky feathers, and general plumage 
soft; rostral portion of cranium moderate; nasals forked, abutting against frontals; 
ecto-ethmoid narrow; vomer scarcely expanded; palatines unnotched; meta- 
sternum slightly concave, perforated by two foramina; ulna longer than second 
metacarpal; phalanges not shortened; shoulder muscles passerine; deep plantar 
tendons characteristic. (Indo-Malayan Subregion and Papuan portion of 
Australian Region.)..................----- Dendrochelidonidze (extralimital).2 
Family MICROPODID. 
THE TRUE SWIFTS.? 
= Micropodide Lucas, Auk, vi, 1889, 13. 
=Apodinae + Chacturinae Hartert, Das Tierreich, Podarg., Caprim., Macropt., 
1897, 62, 63, 65, 80. 
=Cypselide SHarre, Hand-list, ii, 1900, 89. 
Micropodii with the tarsus longer than the first digit; head without 
crest or plumes, flanks without downy or silky feathers, and general 
plumage hard; rostral portion of cranium broad; nasal triradiate, 
overlapping frontals; ecto-ethmoid wide; vomer T-shaped, much 
expanded anteriorly; palatines notched anteriorly; metasternum 
convex, usually entire (with foramina in Tachornis only ?); ulna 
shorter than second metacarpal; phalanges (except ultimate and 
penultimate) very short or obsolete; shoulder muscles and deep 
plantar tendons strictly cypseline. 
Bill very small, broadly triangular, depressed, the culmen rather 
strongly decurved, the maxillary tomium without notch; gape deeply 
cleft, without rictal bristles; nostrils opening vertically, near together, 
longitudinally elliptical or oval, nearly parallel, or more or less 
divergent posteriorly; frontal feathering usually extending over 
lower portion of nasal fosse, sometimes nearly to anterior end of 
nostril, sometimes also extending forward medially, between base 
of nostrils; anterior toes subequal (but one or both of the lateral 
ones usually very slightly shorter than the middle), cleft to the base, 
and covered with skin or feathers (non-scutellate); hallux con- 
spicuously smaller than lateral toes (sometimes less than half as long 
« Dendrochelidonide Lucas, Auk, vi, 1889, 12.—Macropterygide Lucas, Auk, xii, 
1895, 156.—Macropterygine Hartert, Das Tier., Podarg., Caprim., Macr., 1897, 63.— 
Hemiprocnidx Oberholser, Proc. Biol. Soc. Wash., xix, May 1, 1906, 68, in text. 
This very well-characterized family of Swifts comprises a single genus (Hemiprocne 
Nitzsch, Obs. Av. Carot. Com., 1829, 15, type, Cypselus longipennis Temminck; see 
Oberholser, Proc. Biol. Soc. Wash., xix, 1906, 67, 68), containing about seven species. 
The nidification of the Dendrochelidonidz is also peculiar, the nest being attached to 
the upper side of a branch, composed of bits of bark, etc., held together by the bird’s 
saliva, and barely large enough to hold the single egg. They also perch freely upon 
branches, while none of the Micropodide do, so far as known. 
6 As distinguished from the Tree Swifts, family Dendrochelidonide. 
