Book X. Subjectthe nature of birds. (i f.) The ostrich, the phoenix. (iii-vi) Eagles, their species; their nature; when adopted as regimental badges; self-immolation of eagle on maiden's funeral pyre. (vii) The vulture. (viii) Lmmergeier, sea-eagle (1) (ix-xi) Hawks: the buzzard; use of hawks by fowlers where practised; the only bird that is killed by its own kind; what bird produces one egg at a time. (xii) Kites. (xiii) Classification of birds by species. (xiv-xvi) Birds of ill-omen; in what months crows are not a bad omen; ravens; the horned owl. (xvii) Extinct birds; birds no longer known. (xviii) Birds hatched tail first. (xix) Night-owls. (xx) Mars's woodpecker. (xxi) Birds with hooked talons. (xxii-v) Birds with toes: peacocks; who first killed the peacock for food; who invented fattening peacocks; poultrymode of castrating; a talking cock. (xxvi-xxxii) The goose who first introduced goose-liver (foie gras); Commagene goose; fox-goose, love-goose, heath-cock, bustard; cranes; storks; rest of reflexed-claw genus; swans. (xxxiii-v) Foreign migrant birds: quails, tongue-birds, ortolan, horned owl; native migrant birds and their destinationsswallows, thrushes, blackbirds, starlings; birds that moult in retirement: turtle-dove, ring-dove. (xxxvi) Non-migrant birds: half-yearly and quarter-yearly visitors: wit.walls, hoopoes. (xxxvii-xl) Mernnon's hens, Meleager's sisters (guinea-hens), Seleucid hens, ibis. (xli) Where particular species not known. (xlii-v) Species that change colour and voice: the divination-bird class; nightingale, black-cap, robin, red-start, chat, golden oriole. (xlvi) The breeding season. (xlvii) Kingfishers: sign of fine weather for sailing. (xlviii) Remainder of aquatic class. (xlix-li) Craftsmanship of birds in nest-making; remarkable structures of swallows; sand-martins; thistle-finch; bee-eater; partridges. (lii f.) Pigeonsremarkable structures of, and prices paid for; (liv f.) Varieties of birds' flight and walk; footless martins or swifts. (lvi) Food of birds. Goat-suckers, spoon-bill. (lvii) Intelligence of birds; gold-finch, bull-bittern, yellow wagtail. (lviii-lxl) Talking birds: parrots, acorn-pies; riot at Rome caused by talking crow. (lxi) Diomede's birds. (lxii) What animals learn nothing. (lxiii) Birds, mode of drinking; the sultana hen. (lxiv) The long-legs. (lxv f.) Food of birds. Pelicans. (lxvii f.) Foreign birds: coots, pheasants, Numidian fowl, flamingos, heath-cock, bald crow or cormorant, Ted-beaked or Alpine crow, bare-footed crow or ptarmigan. (lxix) New species: small cranes. (lxx) Fabulous birds. (lxxi) Who invented fattening of chickens, and which consuls first prohibited? who first invented aviaries? Aesop's stewpan. (lxxiii-lxxx) Reproduction of birds: oviparous creatures other than birds; kinds and properties of eggs; defective hatching and its cures; Augusta's augury from eggs; what sort of hens the best? their diseases and remedies; kinds of small heron; nature of puff-eggs, addled eggs, wind-eggs; best way of preserving eggs. (lxxxi f.) The only species of bird that is viviparous and suckles its young.