Van Herwaarden was hacking through dense brush on the Indonesian island of Sumatra in 1923 when he encountered a strange creature.
It was "very hairy and very fast," the experienced hunter told a newspaper, but "definitely was not an orangutan. It was large, low on its feet, ran like a man and was about to cross my path when I spotted it."
He started to shoot the creature, then hesitated when he realized how human it looked.
"I suddenly felt I was going to commit murder," the hunter said.
Native guides identified the creature as an orang-pendek, a legendary man-ape. The name means "little man" or "short person." Some say the creature is related to the sedapa or batutut, another mysterious manlike creature of nearby Borneo.
The orang-pendek has been described as standing about 2 1/2 to 5 feet tall. It is said to have a pinkish-brown skin covered by a short, dark fur with a mane of long hair around the face that flows down the back.
Considered more human than apelike, the orang-pendek is said to walk mostly upright and to possess relatively short arms.
Some accounts indicate it walks with its feet reversed so that its toes point backward. According to cryptozoologist John Napier, this peculiar podiatric condition is a long-recurring theme in man-monster stories.
Early European voyagers to Africa, Asia and the New World told of encounters with similar creatures with backward feet. One Spanish explorer said he and his crew were welcomed on a Caribbean island by humanlike creatures with feet pointed backward and long tails.
Skeptics argue that orangutans, gibbons and sun bears may have been mistaken as this creature. But eyewitnesses insist that orang-pendek is a distinct animal and deserves to be found and studied. "We should endeavor to learn more about these creatures," noted British explorer and author Cecil Hathaway. "If they are real, finding them would be one of the most important discoveries in anthropology and could perhaps change popular notions about evolution and how human beings developed."
Recent years have seen an explosion of interest in the orang-pendek because of the writings of British travel writer Deborah Martyr. During a tour of southwest Sumatra in 1989, Ms. Martyr's guide pointed out areas where orang-pendeks were frequently spotted, claiming that he had seen the creature twice.
Mrs. Martyr was skeptical but intrigued enough to investigate further. She was soon taking photographs of the creature's characteristically tiny tracks.
"If we had been reasonably close to a village, I might have momentarily thought the prints to be those of a healthy, 7-year-old child," she reported. "The ball of the foot was, however, too broad, even for a people who habitually wear no shoes."
Mrs. Martyr made plaster casts of the tracks and sent them to the Indonesian National Parks Department. She never saw them again, leaving some to speculate that the evidence was lost or purposely suppressed.
Mrs. Martyr continued her search, making a second career out of stalking the orang-pendek. In 1994, while on an expedition with an organization called Flora and Fauna International, she reported a personal sighting of the creature.
She now claims to have seen orang-pendek three times.
"This little creature is for real," she said. "It's only a matter of time before we capture one and show it to the world."