The Watch-Dog of Merryland is an old man who lives in the Stony Vale at the entrance to Merryland.
His body is covered with hair so thick that when he holds his arms out straight, only his hands can be seen. His hair is so long that it reaches the soles of his feet, and would grow longer if it wasn't worn away by the rough stones of the vale. Not a bit of his body can be seen through the flowing white hair except for the smooth top of his bald head. When the Watch-Dog gets lonely, he counts his whiskers but has not been able to determine whether there are 87,426 or 87,428 because it takes him four months to count them.
Since the Stony Vale is barren, the Watch-Dog never eats. Conveniently he is also never hungry and is unfamiliar with the concept of food.
The Watch-Dog's duty is to keep travelers from passing through the archway into the First Valley of Merryland. He has no ability to enforce his warning, and the river flows toward the arch, so his work is futile. Luckily for him, Dot and Tot were the first and only visitors to Merryland since the Queen assigned him to this post three hundred years earlier.
After Dot and Tot ignored his warning, the Queen visited the Watch-Dog to correct this problem. She ordered him to sit on a rocky shelf above the arch. If any intruders attempt to enter Merryland despite his order, he is to throw himself into the river, thus transforming himself into a rock that will block the passageway. (Dot and Tot of Merryland)