Java Man
Eugène Dubois was a Dutch anatomist and fossil collector. He was the first person to present missing-link fossils that are currently accepted by scientists. Arthur Keith, who had studied Piltdown Man (see below) discussed Dubois and his finds in considerable detail. In 1925 he wrote (9, p.438):

Having finished a training in science and medicine at the University of Amsterdam in 1888, he became a military surgeon, choosing Java for his service. Before setting out for that island, he promised his fellow-students, in all seriousness, to bring home the "missing link." And he made his boast good, for in 1894 he returned with the fossil remains described in the previous chapter. But he also had in his possession then certain other fossil remains of man, of which, for reasons of his own, he said nothing, until May 1920—twenty-six years after his return from Java.

The fossils that Dubois brought back as his missing link were a skullcap, three teeth in a jaw fragment, and a thigh bone. They were found by his workers, and not found together. 

Nearly all anatomists have agreed that the thigh bone looks like that of a modern human. Curiously, it had been broken and healed while the person was still alive. The jaw fragment, as well as two of the three teeth, were more or less ignored and are now mostly forgotten. Keith (9, p. 439-440) explained that in 1890, the year before those fossils were found, Dubois had collected many fossil bones of modern humans in a nearby Java locality. Those bones were preserved in volcanic ash deposited in a lake, together with bones of animals and mussels. Dubois also had access to other bones in Java. A modern chimpanzee skull was sent to him from Berlin (10, p.56). After returning to Amsterdam, Dubois locked up his missing-link fossils for twenty years, and would not allow other scientists to study them. He mislead scientists in many ways, but the hypothesis of outright hoax has never been considered. His missing-link fossils have not been chemically tested.


Peking Man
Davidson Black was an ambitious Canadian physician and anatomist. He spent part of 1914 at the laboratory in England where the Piltdown Man had been studied. He did not have access to those materials, as they were kept hidden from visiting scientists. He must have been impressed with the international attention given to such fossils.

Black determined to find his own missing link, and in 1919 he went to China to do so. A few years later, two human-like teeth and some chipped stones were found in a cave with other animal bones. Black announced these to be a missing link, and used this evidence for all it was worth. The missing link became known as Peking Man. In 1926, he began receiving generous funding for excavations of the cave. More human-like bones were then found.

Black died suddenly in 1934 at the age of 49. Detailed descriptions of the bones were then published by his successor Franz Weidenreich (14). He concluded that these and the Java fossils were from a race of fully evolved human, like Neanderthal Man. Furthermore, Weidenreich (14, p. 216) was convinced that Piltdown Man was an error, being the skull of a human and the jaw of an orangutan. It may have been his published skepticism that pressured scientists to allow the chemical testing of the Piltdown fossils.

In 1941, all the fossils of Peking Man were mysteriously lost and have never been found. There is no material that is available for chemical testing or dating. Today, Java Man and Peking are generally assigned to the missing-link species Homo erectus.