"Lacking large segments of the anatomical jigsaw puzzle, Smith Woodward had to make some guesses as to how the pieces he had might relate to each other. Apparently misidentifying some minor anatomical landmarks on the interior of the cranium, he assembled a skull that not only was erroneously small (just over 1,000 cubic centimeters) but also appeared to have certain primitive anatomical features. This reconstruction deeply impressed Elliot Smith. Sir Arthur Keith, however, challenged the accuracy of the reconstruction and did one of his own, eschewing the errors Smith Woodward had committed. Keith's version not only was much bigger (about 1,500 cubic centimeters), but also lacked the primitive features erroneously present in Smith Woodward's… "The Exposure of the Piltdown Fraud," lecture at the Royal Institution, London, 20 May 1955
'Why did not [Keith's] correction immediately raise suspicions of the authenticity of the Piltdown fossils?' asked Le Gros Clark. 'Because of its personal nature the controversy [between Keith and Smith] certainly clouded the issues and befogged the atmosphere of scientific discussion…
In his day Elliot Smith's authority carried great weight (and rightly so, for he was a very eminent anatomist), so that not only did he persuade himself that his original interpretation of the skull and endocranial cast had been fundamentally right, he also seems to have persuaded biologists in general that this was so.' But in spite of their differences of opinion, both Keith and Elliot Smith continued to accept Piltdown Man as a vindication of their own ideas, each for his own different reasons. Keith, who viewed the skull as essentially modern in form, saw it as a confirmation of the antiquity of modern types of man. At the same time, Elliot Smith claimed the cranium to be distinctly primitive in form."
 Roger Lewin (noted science journalist), Bones of Contention (New York, NY: A Touchstone Book published by Simon & Schuster Inc., 1987), pp. 74-75
The Piltdown Man Fraud
The Taung Skull: 'missing link'?