. ▁The ▁A pat osa urus ▁sk ull , ▁long ▁thought ▁to ▁be ▁similar ▁to ▁Cam ar as aur us , ▁is ▁much ▁more ▁similar ▁to ▁that ▁of ▁Di pl od ocus . ▁A pat osa urus ▁was ▁a ▁generalized ▁browser ▁that ▁likely ▁held ▁its ▁head ▁elev ated . ▁To ▁light en ▁its ▁verte bra e , ▁A pat osa urus ▁had ▁air ▁sac s ▁that ▁made ▁the ▁b ones ▁internally ▁full ▁of ▁holes . ▁Like ▁that ▁of ▁other ▁di pl od oc ids , ▁its ▁tail ▁may ▁have ▁been ▁used ▁as ▁a ▁wh ip ▁to ▁create ▁loud ▁no ises . ▁ ▁The ▁sk ull ▁of ▁A pat osa urus ▁was ▁confused ▁with ▁that ▁of ▁Cam ar as aur us ▁and ▁Bra ch ios aur us ▁until ▁ 1 9 0 9 , ▁when ▁the ▁hol ot ype ▁of ▁A . ▁l ou is ae ▁was ▁found , ▁and ▁a ▁complete ▁sk ull ▁just ▁a ▁few ▁meters ▁away ▁from ▁the ▁front ▁of ▁the ▁neck . ▁Henry ▁Fair field ▁Os born ▁disag re ed ▁with ▁this ▁association , ▁and ▁went ▁on ▁to ▁mount ▁a ▁ske leton ▁of ▁A pat osa urus ▁with ▁a ▁Cam ar as aur us ▁sk ull ▁cast . ▁A pat osa urus ▁ske let ons ▁were ▁mounted ▁with ▁spec ulative ▁sk ull ▁cast s ▁until ▁ 1 9 7 0 , ▁when ▁Mc Int osh ▁showed ▁that ▁more ▁robust ▁sk ull s ▁assigned ▁to ▁Di pl od ocus ▁were ▁more ▁likely ▁from ▁A pat osa urus . ▁ ▁A pat