174 ON THE CLASSIFICATION OF BIRDS. 
with its keel uppermost. Some authors enumerate thre¢ 
and others only one species ; but they are all peculiar t 
the New World. The spoon-bills (Platalea) show a 
different, but a no less singular, form of beak, from 
which their name has been derived. The storks ( Ci- 
conia L.) are among the largest of the heron family ; or 
species (Ciconia gigantea) measuring, when standing 
erect, near five feet and a half: they are-social and useful 
birds ; and from destroying vast numbers of reptiles and 
other vermin, are encouraged, in many countries, to build 
on the habitations of man: the chin and eyes are bare 
of feathers; but in Mycteria, which possibly enters 
into this family, the greatest part of the head ind 
neck is entirely bare: one species inhabits America, 
one Asia, and one Australia. The tufted umbre- 
forms the African genus Scopus, and is the only species” 
known ; the plumage is particularly soft, and the back 
of the Hestl furnished with a lax tuft of feathers: this” 
is obviously allied to the open-bills (Anastomus IIl.), a 
singular form, remarkable for a thick and very powerful 
bill, gaping inthe middle. It is impossible to divine for 
what purpose this structure, altogether unique among 
birds, is intended to perform, since their economy has 
never been explained. These are the principal genera 
which appear to enter into this family, of which the 
herons and cranes form the two most typical groups. 
(196.) The Cuarapriap#, or plovers, as already 
intimated, form the subtypical family of this order. It 
seems connected to the Ardeade through the medium of 
the cranes ; the thick-knees, Hdicnemus; or, probably, 
by the genus Cariama of Latham,—a form we have never 
minutely examined. In this comprehensive group, the 
feet are long and slender, formed for great speed; the 
toes are short, and the hinder one is generally wanting ; 
the wings are long, and consequently the powers of flight 
are very great. Herons and rails seek the most secluded 
recesses of marshy shades. Plovers and sandpipers, on — 
the contrary, live only on sandy and unsheltered shores, 
or on exposed commons ; they congregate in flocks, and. 
