The head is entirely naked in _Meleagris_, and is covered with caruncles, an erectile process hanging from the forehead; a pair of long fleshy horns above the eyes distinguish _Ceriornis_, which has in addition a large wattle on the throat; a comb of similar substance is accompanied by a single median or two pairs of lateral wattles in _Gallus_; while the sides of the face, the orbits, or the fore-neck, are bare in many genera. The male of _Lobiophasis_ has the head nearly naked, with no less than three pairs of wattles; though the female has but one rudimentary pair of the latter, and only the cheeks unfeathered. In all these cases the skin and outgrowths are red or blue. The head and neck are bare in the Numidinae, except for a crest in _Guttera_, a crescentic nuchal band of feathers in _Acryllium_, and a line of plumage down the crown in _Phasidus_; wattles occur at the angles of the gape in _Guttera_ and _Numida_, both these and the naked skin being blue and red throughout the Sub-family, save in _Phasidus_, where the latter is yellow, and in _Agelastes_, where it is red and white. The bony casque of _Numida_ is red or horn-coloured. The Tetraoninae have merely a little red or yellow skin over the eye. In females all the fleshy outgrowths are much smaller or absent, throughout the Family. Air-sacs of orange skin lie below the side-feathers of the neck in the males of _Centrocercus_, _Dendragapus_, and _Tympanuchus_, and become visible when inflated; they are supposed to produce the booming ventriloquistic sound, uttered in the breeding season. _Bonasa_ has a naked space in a similar position, but its drumming is stated to be caused by the wings. _Pedioecetes_ can hardly be said to have air-sacs, yet it also drums, while the exact nature of the corresponding sounds made by _Tetrao urogallus_ and _Lyrurus tetrix_ is uncertain. The "gobble" of the domestic Turkey is a parallel instance, in so far as it is uttered during excitement.