Hmmmm,symantics,
Brontosaurus excelsus was named in 1879 by Marsh, based on a rather good specimen. Unfortunately, two years earlier he'd named some much scrappier remains with the rather less resonant name Apatosaurus ajax.
In 1903, Elmer Riggs' re-examination of Marsh's specimens led him to conclude that they represented the same genus (although see below), meaning that the names were synonyms. In such cases, the ICZN (International Commission on Zoological Nomenclature, see
http://www.iczn.org/ mandates that the oldest name has priority - which means that the rather dull Apatosaurus (``deceptive lizard'') wins out over the much more resonant ``Brontosaurus'' (``thunder lizard'').
So Haz, gonny get back to work and I'll have a real big beer 2.
