KELPY, KELPIE
Scottish Folklore
This is the fearsome, malevolent, semi-supernatural water monster of Scottish folklore. Although it could assume the form of a rough, shaggy old manor a handsome young man, the KELPY mostly took the form of a black or grey horse with flashing eyes and silken coat. It could be identified by the green rushes that always clung to it's hair. The KELPY was to be found on the shores of the lochs, at fords, and at ferry points. To see a KELPY is considered a portent of drowning or other waterborne catastrophe. In human form it could leap on to the horse behind the rider and crush the terrified traveler to the point of death. It would appear to unsuspecting young women as a lover, eventually abducting and then devouring them under the water, The KELPY would also entice wandering children or unwary men to mount him in the guise of a sleek horse on the side of the loch. The monster would gallop off into the water, dragging down his victims and devouring all but the entrails, which would float to the surface. If anyone could get a bridle over the KELPY'S head, it was said that it would do the work of several horses. The KELPY was also known to keep the waterwheels of the mills turning at night; he was just as capable of destroying them too. A legend tells how the LAIRD OF MORPHIE once bridled once bridled a KELPY and made it work hard, dragging the stones for the building of his castle. On completion the released monster cursed the laird never to enjoy the building, and the curse remained with the Grahams of Morphie ever since.
Source: Giants, Monsters, and Dragons: An Encyclopedia of Folklore, Legend, and Myth