'; ?>
click to enlarge
The Dinosaur beds are exposed along the foothills of the Big Horn from Middle Powder to near Clarks Fork in the Yellowstone in some places however they are pinched out or grass covered as is for instance traveling north the last exposure is seen at Grenb or a few miles north of there and is not again encountered till near the head of the Little Horn River The relation of the Triassic Marine and Fresh water Jurassic is the same throughout their exposure. They have the same thickness The invertebrates in the marine Jurassic occupy exactly the levels wherever found