. The royal natural history. S-CXoi^c. del ct Sc. The diurnal birds of prey were long classed in a single group with the owls and the ospreys, but first the former and then the latter were divided off; and there is little doubt that view is correct, although, to our thinking, the merlins. ospreys appear to connect the two groups very intimately. Exclusive of the ospreys, the diurnal birds of prey, as they may be convenientl}^ designated, include falcons, hawks, kites, eagles, buzzards, harriers, and vultures, together with the so-called secretary-bird of Africa and the American vultures ; the

RM2AFRBTH–. The royal natural history. S-CXoi^c. del ct Sc. The diurnal birds of prey were long classed in a single group with the owls and the ospreys, but first the former and then the latter were divided off; and there is little doubt that view is correct, although, to our thinking, the merlins. ospreys appear to connect the two groups very intimately. Exclusive of the ospreys, the diurnal birds of prey, as they may be convenientl}^ designated, include falcons, hawks, kites, eagles, buzzards, harriers, and vultures, together with the so-called secretary-bird of Africa and the American vultures ; the

The royal natural history . flower-animalcule (magnified 200 times). 443 WORMS. The Thread-Worms, or Round-Worms,—Class Nematohelminthes. These worms are characterised by having a thread-like body, covered withtough, elastic integument, but usually showing no distinct traces of being dividedinto segments like those of leeches and earth-worms, and possessing no trace oflimbs. The sexes are generally distinct. The group is divided into the threeorders Acanthocephali, Nematoidea, and Chaetognatha. Spiny-Headed Thread-Worms,—Order Acanthocephali. In this order is contained the single genus Echinor

RM2AN4B26–The royal natural history . flower-animalcule (magnified 200 times). 443 WORMS. The Thread-Worms, or Round-Worms,—Class Nematohelminthes. These worms are characterised by having a thread-like body, covered withtough, elastic integument, but usually showing no distinct traces of being dividedinto segments like those of leeches and earth-worms, and possessing no trace oflimbs. The sexes are generally distinct. The group is divided into the threeorders Acanthocephali, Nematoidea, and Chaetognatha. Spiny-Headed Thread-Worms,—Order Acanthocephali. In this order is contained the single genus Echinor

$. The royal natural history. ^ arc birds of universal distribution, veiy VOL. IV.— I PICARIAN BIRDS. varied in form and habits, some being entirely parasitic, while others build nests.They are divided into six subfamilies; and while the usual number of tail-feathersis ten, in one group {Crotophagince) only eight are present; the other subfamiliesbeing well distinguished. The first representatives of the typical subfamily Cuculince arethe crested cuckoos, which, in common with the other members ofthe group, have pointed wings, and are strong fliers. The genus is distinguished Crested Cuckoos..$

RM2AFTMGP–. The royal natural history. ^ arc birds of universal distribution, veiy VOL. IV.— I PICARIAN BIRDS. varied in form and habits, some being entirely parasitic, while others build nests.They are divided into six subfamilies; and while the usual number of tail-feathersis ten, in one group {Crotophagince) only eight are present; the other subfamiliesbeing well distinguished. The first representatives of the typical subfamily Cuculince arethe crested cuckoos, which, in common with the other members ofthe group, have pointed wings, and are strong fliers. The genus is distinguished Crested Cuckoos..