ARDEID, HERONS. 265 
_ the beautiful crests and dorsal plumes that ornament many species, but which, as a 
Tule, are worn only during the breeding season. These features will suffice to deter- 
mine the Ardeide, taken in connection with the more general ones indicated under 
head of Herodiones, and the details given beyond. 
The boat-billed heron of Central America, with a singular shape of the bill that 
has suggested the name, and the four pairs of powder-down tracts, constitutes one 
subfamily, Cancromine. The still more remarkable Baleniceps rex, of Africa, with 
an enormous head and bill, thick neck, and one pair of such tracts, is probably 
assignable here as a second subfamily, Balenicepine ; but it approaches the storks, 
and may form a separate intermediate family. The disputed cases of Rhinochetus, 
Burypyga and Scopus have been already mentioned; these five forms aside, the 
herons all fall in the single 
Subfamily ARDEINA. True Herons. 
Bill longer than head, straight, or very nearly so, more or less compressed, acute, 
cultrate (with sharp cutting edges) ; upper mandible with a long groove; nostrils 
more or less linear, pervious. Head narrow and elongate, sloping down to the bill, 
its sides flattened. Lores naked, rest of head feathered, the frontal feathers 
extending in a rounded outline on the base of the culmen, generally to the nostrils. 
- Wings broad and ample; the inner quills usually as long as the primaries, when 
closed. Tail very short, of twelve (usually), or fewer soft broad feathers. Tibize 
naked below, sometimes for a great distance. Tarsi scutellate in front, and some- 
times behind, generally reticulate there and on the sides. Toes long and slender ; 
the outer usually connected with the middle by a basal web, the hinder very long 
(for this order), inserted on the level of the rest. Hind claw larger and more 
curved than the middle one (always?) ; the middle claw pectinate. 
The group thus defined offers little variation in form; all the numerous genera 
now in yogue have been successively detached from Ardea, the typical one, with 
which most of them should be reunited. The night herons (235-6) differ 
~ somewhat in shortness and especially stoutness of bill; while the bitterns (237, 
and the South American genus Tigrisoma) are still better marked. There are 
about seventy-five species, very generally distributed over the globe, but especially 
abounding in the torrid and temperate zones. Those that penetrate to cold 
countries in summer, are regular migrants; the others are generally stationary. 
They are maritime, lacustrine and paludicole birds, drawing their chief sustenance 
from animal substances taken from the water, or from soft ground in its vicinity ; 
such as fish, reptiles, testaceans and insects, captured by a quick thrust of the 
spear-like bill, given as the bird stands in wait or wades stealthily along. In 
conformity with this, the gullet is capacious, but without special dilation, the 
stomach is small and little muscular, the intestines are long and extremely 
slender, with a large globular cloaca, and a cecum. Herons are altricial, and 
generally nest in trees or bushes (where their insessorial feet enable them to 
perch with ease) in swampy or other places near the water, often in large 
communities, building a large flat rude structure of sticks. The eggs vary in 
number, coincidently, it would seem, with the size of the species; the larger 
herons generally lay two or three, the smaller kinds five or six; the eggs are 
somewhat elliptical in shape, and usually of an unvariegated bluish or greenish 
shade. The voice is a rough croak. The sexes are nearly always alike in color 
(remarkable exception in gen. 238); but the species in which, as in the bittern, 
KEY TO N. A. BIRDS. 34 
