Brachylophosaurus was your typical hadrosaur. At 25 feet in length and about 2 tons in weight, it was average in size. Brachylophosaurus is known from very complete remains including a number of dinosaur mummies. One of the best was nicknamed Leonardo. Leonardo not only had preserved skin like some dinosaur mummies, but also it's internal organs. Brachylophosaurus lived about 75 million years ago in North America.