536 PASSERIFORMES : VIREONIDAE CHAP. 
black and chestnut species, with a compressed, swollen and hooked 
steel-blue beak exhibiting a pearly interior, should perhaps stand 
in a separate Family, Lurycerotidae, and not with the Shrikes. 
Fam. XVII. Vireonidae.—The small group of “ Greenlets” 
ranges from Winnipeg and Nova Scotia to Argentina. The com- 
pressed or depressed beak varies from stout and strongly hooked, 
as in Vireolanius and Cyclorhis, to small and comparatively weak 
as in Hylophilus ; both mandibles being notched, and the gape 
bristly. The metatarsi are usually short and robust with slightly 
united anterior toes, but are longer and more feeble in Vireo ; the 
wings may be elongated and pointed, as in Vireosylvia, or abbre- 
viated and roundish, as in Vireo and Neochloe ; the tail is normally 
short and even, with narrow feathers, but 1s rounded in Neochloe. 
The frontal feathers are somewhat erect. The coloration is olive, 
or green and grey above—with a black, brown, ashy, or reddish cap 
—and is grey, whitish, or yellow beneath; the wing frequently 
exhibits white bands, and the head white, dusky, or rufous 
stripes. White or yellow orbital rings occur in Lanivireo, a 
red-brown tail in Hylophilus ochraceiceps, a blue crown in 
Vireolanius pulchellus, a chestnut pectoral band in V. melit- 
ophrys. The bill and feet are sometimes red; the eyes white, red, 
or yellow. The sexes frequently differ in colour. 
These active and fearless birds inhabit forests up to an altitude 
of ten thousand feet, as well as ravines, swamps, or even streets 
of towns; they are usually observed in pairs among the higher 
branches of trees, creeping and hanging to the twigs, or chasing one 
another about in play. Seldom do they seek the ground, but they 
take fairly long flights, and dart out after passing insects, which, 
with the larvae and a few berries and seeds, form the diet. The 
continuous song consists of loud, reiterated, flute-like notes, supposed 
in one case to resemble “ Whip-Tom-Kelly ”; some forms also utter 
harsher chirps or mews. The nest, a deep, firm cup of leaves, grass, 
bark, lichens, spiders’-webs and cottony materials, lined with fibres, 
fir-needles, delicate stems, or rarely down, is supported by some hori- 
zontal fork, over which the rim is commonly turned; the four or five 
eggs are white, generally spotted with red-brown, black, or purplish. 
Fam. XVIII. Sittidae.—The Nuthatches, though closely allied 
to the Paridae, show a certain affinity to the Certhiidae (p. 571). 
Typically they are stout lttle birds with long, pointed wings, and 
short nearly square tails; the bill is fairly long and strong, and is 
oOo? 
