Eighteen months ago, I noted that the Carnegie Museum’s Diplodocus mount has no atlantal ribs (i.e. ribs of the first cervical vertebra, the atlas). But that the Paris cast has long atlantal ribs — so long the extend past the posterior end of the axis. There were two especially provocative comments to that post. First, Konstantin linked to a photo of the Russian cast (first mounted in St. Petersburg but currently residing in Moscow).