Diplodocus longus (Marsh, 1878); or potentially, Diplodocus carnegii (Hatcher 1901)
While scientists and taxonomists debate the value of replacing the first (based on several vertebrae and some leg material) with a holotype that includes far, far more complete material, enjoy instead this large, adult, and robust (relatively speaking) diplo skull.
This illustration represents a composite of various skull material ranging in age, and possible taxonomic confusion. Unlike the other illustration (available here: https://qilong.wordpress.com/diplodocus-longus-skull/) this skull aimed to be based on actual skull material and where possible multiple views. For instance, better attention is paid to the palatal bones, which better rewards reconstruction of some soft-tissues. The reconstruction principally follows CM 11161, which may itself not belong to D. longus at all.
The Bite Stuff 
Shouldn’t CM 11161 be more likely Diplodocus hallorum based on the fact the skull was found in the Dinosaur National Monument/Carnegie Quarry, where D. hallorum was found?
Either way, interesting that there are differences between CM 11161 and USNM 2672.