Re: Brontosaurus/Apatosaurus

[twilliams@canr1.cag.uconn.edu]

> _Apatosaurus_ has been used almost exclusively for the genus for most of the
> twentieth century. It is not at all an "unused" name.

Something which bugs me is that the holotype of _Apatosaurus_ is 
actually an immature specimen - in fact, the characters which Marsh 
originally used to differentiate _Apatosaurus_ from _Brontosaurus_ 
(such as lower no. of sacral vertebrae) are juvenile characters.

I wonder if the holotype of _Apatosaurus ajax_ has enough characters
to diagnose the genus and/or the species, and distinguish it from _excelsus_. 
If not, then _Apatosaurus_ is a nomen dubium, and _Brontosaurus_ 
would be resurrected.