The Green Hound of the Highlands

The Cu Sith ("fairy dog") is a supernatural hound of Scottish Highland and Hebridean tradition, described with unusual precision: about the size of a young bull or a large calf, with a shaggy dark-green coat, a long tail coiled or braided on its back, and enormous paws that leave prints in mud and snow. It moves silently, in a straight line, and hunts by day; but its bark is the danger, for it gives three great bays as it ranges, and a traveller who has not reached safety by the third is said to be overtaken. In some accounts its special errand is to carry off nursing mothers to the fairy knolls to suckle fairy children.

The Cu Sith belongs to the wide British and Irish family of spectral dogs, the Black Shuck of East Anglia, the Barghest of Yorkshire and others, most of which are omens of death; but its green colour and its silent, purposeful gait are distinctively its own. It is chiefly a creature of oral Gaelic folklore rather than of any written mythological text.