154 FALCONIFORMES CHAP. 
aries ; the wide crest, short rectrices, red cere, lores and feet, render- 
ing it most remarkable. /H./ewconotus is hardly more than a creamy- 
backed variety. It sails aloft in powerful style, and dashes hke 
lightning upon the snakes, mammals, and lizards, which form its 
prey ; the nest of sticks is placed in trees or rocks, and contains, 
it is said, from two to four white eggs. The crested Lutriorchis 
of Madagascar, and Dryotriorchis of the Gold Coast, short of wing 
but long of tail, should probably be placed here. A fine broad 
crest also adorns Spilornis, of which genus some seven members 
occur in the Indian Region, and the Celebes group. S. undulatus 
(cheela), extending from India to China, has the head black and 
white, the remaining plumage brown, with whitish markings 
above, round white spots below, and a broad leght band across 
the white-tipped tail. S. swlaénsis of the Sula Islands differs in 
being barred beneath; S. holospilus of the Philippines has the 
whole body spotted. These arboreal forms live upon snakes, frogs, 
insects, and birds, the last of which they hunt in pairs, converg- 
ing gradually on the victim from each side: the note is mournful ; 
the small nest of twigs, ined with grass or leaves, is placed in 
trees; the two eggs are rufous or white with red markings. 
The slender Polyboroides typicus, of most of the Ethiopian 
Region, combines the appearance of a Harrier with that of a 
typical Hawk; it is grey with white tips to the black remiges and 
rectrices, and shews black and white bars on the lower breast and 
abdomen. A whitish band crosses the tail, while the naked cheeks 
and cere are yellow. LP. radiatus of Madagascar is more silvery. 
Resembling the following group in habits, these birds prefer grass- 
lands, especially when newly burnt, take comparatively short 
flights, and rest more frequently on trees or stumps. They are 
said to be able to bend the tibio-tarsal joint either way. 
Circus, ranging over nearly the whole world, comprises. some 
seventeen species, in most of which the sexes differ in coloration 
an unusual fact in Raptorial forms. They are graceful and soft- 
plumaged, with long legs, wings, and tail, the partial facial ruff 
creating a likeness—superficial and not warranted by structure 
—to the owls. Non-arboreal and by nature shy, they may be seen 
hovering or circling aloft, or systematically beating over the flats 
with buoyant untiring flight, the pinions flapping slowly and 
regularly, and exposing a broad surface to the air. They can, 
however, move with rapidity, and approach their breeding-quarters 
