In 1866 Haeckel predicted that a transitional substance would be found on sea floors, to fill the gap between non-living matter and life. So certain was he that he even named it monera ahead of time. Mud was dredged from the sea floor and called Bathybius haeckelii by Huxley, and monera was proclaimed as a fact.
In 1875 chemists from the boat, HMS Challenger, which did the dredging, determined that the substance was actually gypsum - a rock! This fact was not translated into English and made public until 1971 - nearly 100 years later!
http://www.baptistlink.com/godandcountry/html/faker_haeckel.0
"This fact was not translated into English and made public until 1971 - nearly 100 years later!"
Not sure about this "fact". Looks like Huxley admitted the error.
"Bathybius was not a fossil, but a putative primitive organism that was "discovered" living on ocean floors. It was a gelatinous layer with tiny granules in it that were sometimes observed to move around. In 1868, Thomas Huxley named it Bathybius haeckelii, because it seemed much like Ernst Haeckel's idea of a very primitive organism -- Urschleim or ancestral slime.
However, during the Challenger expedition (1872-1875), chemist John Buchanan noticed that Bathybius appeared in ocean-floor samples preserved with alcohol, but not those in normal seawater. After some experimentation, he discovered that he could produce Bathybius by adding alcohol to an ocean-floor sample; this "organism" turned out to be a precipitate of calcium sulfate. When the expedition returned, Huxley "ate leek", but otherwise took it in stride. For more details, check out this Huxley archive (http://aleph0.clarku.edu/huxley/guide9.html)."
From: http://www.evowiki.org/index.php/Fake_fossils