Albany and Carbon counties, in the south central part of the State. The bones are usually 

 found in banks of clay or marl, but occasionally in beds of sandstone. It is not an unusual 

 thing to find a bone bed four or five feet in thickness, with the bones so close together and so 

 mixed up that it is almost impossible to take them out and restore them to a normal place in 

 the body. 



At one time in the history of Wyoming, geologists say that the State had numerous fresh- 

 water lakes and a climate that was semi-tropical. At this time, these animals are believed 

 to have inhabited these lakes and swamps in myriads. The animals sank into the mud in 

 dying and their bones were covered over with other deposits and became petrified. The large 

 beds are found where at one time are supposed to have been the mouths of great rivers, the 

 animals after death having floated down these rivers to where they were deposited in these 

 estuaries, thus accounting for the vast deposits in certain places. 



It is believed that through the geological ages these animals became covered with 

 perhaps 20,000 feet of rock. The process by which the Rocky Mountains were formed tilted 

 these beds, and subsequent erosion has thus brought to light the burying grounds of millions 

 of years ago. 



The history of this reptilian age in which the Dinosaur lived has been faithfully, although 

 not fully, written in Nature's unmistakable hieroglyphics, found in these vast burying 

 grounds. The animals of the period, although all lizard-like, were yet widely different in 

 character. The seas were inhabited by fishes, turtles, and sea serpents. On the land were 

 herbivorous, carnivorous, jumping, flying, and armored animals, all reptilian in their nature. 

 Associated with these were a few mammals about the size of a modern mouse, and a few 

 primitive birds. 



11 



