468 SYSTEMATIC SYNOPSIS —PICABIJE— CUCULIFOBMES. 
24. Family TROGONID^ : Trogons. 
Feet zygodactyle by reversion of the second toe (see p. 127). The 
base of the short, broad, dentate bill is hidden by appressed antrorse 
feathers ; the wings are short and rounded, with falcate quills ; the 
tail is long, of twelve broad feathers ; the feet are very small and 
weak. The general plumage is soft and lax, the skin tender, the 
eyelids lashed. A well-marked ftimily of about 50 species and 
perhaps a dozen genera, chiefly inhabiting tropical America. They 
Fig. 318. — Head of Cop- ^^'^ gorgeous colors, and among them are found the most magni- 
per-tailed Trogon, nat. size. ficent birds of this continent (fig. 317). 
144. TROGON. (Gr. rpwyo)!/, trogon, a gnawer : alluding to the dentate bill.) The leading genus, 
to which the above characters fully apply. 
423. T. ambi'guus. (Lat. amhiguus, ambiguous, as doubtfully distinct from T. mexicanus. Fig. 318.) 
Copper-tailed Trogon. Metallic golden-green ; face and sides of head black ; below from 
the breast carmine; a white collar on the throat ; middle tail-feathers coppery-green, the outer 
white, finely variegated with black ; quills edged with white. Length about 11.00 ; wing 5.25 ; 
tail 6.75. Valley of the Lower Rio Grande, and southward. 
[Family MOMOTID^ : Sawbills. 
Feet syndactyle by cohesion of third 
and fourth toes (p. 129) ; toinia serrate. 
A very small family of tropical American 
birds, comprising about 15 species, none 
having really rightful place here ; but 
the Momotus coeruleiceps (fig. 319) comes 
near our border, and is included to illus- 
trate the suborder. In this species, the 
central tail-feathers are long-exserted, 
and spatulate by absence of webs along 
a part of the shaft — a mutilation effected, 
% it is said, by the birds themselves; the 
Fig. 319. — Head of Blue-beaded Saw-bill, nat. size. bill is about as long as the head, gently 
curved; the nostrils are rounded, basal, exposed; the wings are short and rounded; the tarsi 
are scutellate anteriorly. It is greenish, with blue head. IMexico.] 
25. Family ALCEDINID^ : Kingfishers. 
Feet syndactyle by cohesion of third and fourth toes (p. 129, fig. 44) ; tomia simple. Bill long, 
large, straight, acute (rarely hooked) ; somewhat fissirostral," the gape being deep and wide. 
Tongue rudimentary or very small. Nostrils basal, reached by the frontal feathers. Feet very 
small and weak, scarcely or not ambulatorial ; tibiae naked below ; tarsi extremely short, reticu- 
late in front ; hallux short, flattened underneath, its sole more or less continuous with the sole 
of the inner toe ; soles of outer and middle toe in common for at least half their length ; inner 
toe always short, in one genus rudimentary, in another wanting (an abnormal modification). 
Developed toes always with the nonnal ratio of phalanges (2, 3, 4, 5 ; p. 127) ; middle claw not 
serrate. Wings long, of 10 primaries. Tail of 12 rectrices, variable in shape. 
^' The Kingfishers form a very natural family of the great Picarian order, and are alike 
remarkable for their brilliant coloration and for the variety of curious and aberrant forms which 
