The bittern is a bird of singular appearance. On the wing he resembles the heron, but it is a rare thing to see him abroad in the daytime. He is strictly nocturnal in habits, and passes the daylight hours concealed in thick reed-beds in extensive marshes. His buff and yellow and chestnut colour, mottled and barred and pencilled with black and brown, gives him a strange tigrine or cat-like appearance; it is a colouring well suited to his surroundings, where yellow and brown dead vegetation is mixed with the green, and the stems and loose leaves of the reeds throw numberless spots and bars of shade beneath. Secure in its imitative colouring, the bittern remains motionless in its place until almost trodden upon. Its active life begins in the evening, when it leaves its hiding-place to prey on fishes, eels, frogs, voles, small birds, and insects, and every living thing it finds and is able to conquer with a blow of its sharp, powerful bill. When flying he utters a harsh, powerful scream, and he has, besides, a strange vocal performance, called ‘booming’--a sound that resembles the bellowing of a bull. Formerly, when the bittern was a common bird in England, this extraordinary evening performance was the subject of some superstitious notions, and it was commonly believed that, to produce so great a volume of sound, the bird, when screaming, thrust its beak and head into the water. Thus, in Thomson’s ‘Seasons’ we read:-- The bittern knows his time, with, bill submerged, To shake the sounding marsh. In March or April the nest is made on the ground, among the thick reeds, and is formed of weeds, sticks, and rushes. The eggs are four in number, of an olive-brown colour, sometimes with a greenish shade. Besides the two species described there are no fewer than eight herons in our list of British birds, most of these being very rare stragglers to our shores:-- Purple heron (_Ardea purpurea_) is a straggler from the continent of Europe; it breeds in Holland. Great white heron (_Ardea alba_).--Eight examples of this species, a straggler from South-eastern Europe, have been obtained in this country. Little egret (_Ardea gazetta_).--A waif from Southern Europe; it also inhabits Africa, Asia, and Australia. Buff-backed heron (_Ardea bubulcus_).--Inhabits Southern Europe; three examples have been obtained. Squacco heron (_Ardea ralloïdes_).--From Southern Europe; occasionally seen on migration in England. Little bittern (_Ardetta minuta_).--This bittern almost deserves to rank as a British species, as it is of somewhat frequent occurrence, and has been known to breed in the Broads of Norfolk, and in other localities in Great Britain. It is a summer visitor to most countries in Europe.