In reply to Futura and Twentieth Century:
Could you point out specifically what to look for? I know there's more *totally blanking out on the term right now* "thinning" where the bowls meet the stems but not a large enough difference that I would be able to ID the typeface just by looking at one without comparison to the other. I need something I can tell easily just by looking at one without comparing the two. For example one thing I found was that the arm of the 'r' is cut off vertically in Tw Cen while in Futura it cuts off at an angle