The Brontosaurus Rex was recently unearthed in what is present day Arizona, at the bottom of what was a giant lake.  The monster most likely attempted to cross the thousand mile lake in search of food, but came up against strong winds and high seas.  As was the fate of many Brontosaurus Rexs of this time, the swim proved too far, and they succumbed to exhaustion around the middle of the lake.  The B-Rex, as it has affectionately been nicknamed has an interesting physical construction consisting of a long tail, four sturdy legs, and surprisingly two seemingly useless forearms mid way up its neck.  This dinosaur was most likely a carnivore that would occasionally snack on vegetables if it had to.  The B-Rex's long tail and overall extended body would have made it an adept swimmer if pressed, and it looks like 500 miles was its marine range.  On land, the B-Rex covered considerably more ground, with a migratory range of 2000 miles.  The dinosaur spent North American winters in Mexico and summered in what looks like San Francisco.  An aggressive carnivore, the B-Rex had the ability to run, however awkward and unwieldy its physical construction was, reaching speeds of 30 miles an hour!  It should be noted that a wide open, long, flat surface was needed, as it took some time to get 200 tons of dino rollin.  Once in motion, the B-Rex was amazingly agile and dangerous.  Coupled with a powerful tail used for balance and attack, and a large, powerful head containing massive teeth, the B-Rex could chase down prey and eat it on the run.  Its massive weight did announce its coming, much like an earthquake or volcano.  Most of its prey was snuck up upon, the B-Rex was known for swooping in from tree tops, descending on sleeping triceratops with vigor.  The above drawing by noted professionals in the field, helps to illustrate this amazing lost animal.