Poortvliet was a famous Dutch painter, best known for his part in the creation of the Gnome children’s books. He was also both a hunter and a naturalist, and spent a lot of time creating vivid and educational illustrations of the wildlife around him in Europe. From wikipedia: Poortvliet saw himself as a characteristic narrator. His drawings told the tale, and at most he added a short caption.
Images from The Living Forest: The World of Animals.