‘The Satrass’ or Caledonian Man Monkey that is mentioned in an old ledger called the History of Ancient Caledonian that was printed in 1879 by John MacLaren.

https://archive.org/stream/historyofancient00macluoft/historyofancient00macluoft_djvu.txt

In pages 29 and 30 he shares a poem that centres on the grandson of M’Intyre, who rebelled against Gaul. Here’s an excerpt,

“Now the grandson of M’Intyre, who rebelled in Gaul, and broke off from Lazarus and Daniel, went to Birnam, being there oppressed with Satrass, or Man Monkey, of a prodigious size, was forced to leave that place and come to Saint Laurence of Dundee for protection”.

This race of Man Monkey lived chiefly on a diet of fish. They had no language, but seemed to understand each other and communicate by fearful screaming and roaring. They were very mischievous to cattle, and the inhabitants of the villages became afraid of them. There was nothing that frightened them except fire; and when the inhabitants heard them nearby, they would set fire to the heath to frighten the Men Monkeys away. Through the course of time, however, they wore back to the forest.