in.iierial was washed downslream aiul ilepositfJ In-re but, 

 allcrnalins with iheso. were \onf, pcriixis when fine sill and nuid 

 accunuilated This was in ihe middle of whai we now call the 

 age of reptiles, or the Jurassic Period, and the sandstones then 

 formed make up what we now call the Morrison beds. Durinjj 

 floods, the corpses of the animals that inhabited both this delta 

 and the surrounding lands were from time to Imie carried along 

 by the waters, and were deposited on sand bars, just as the 

 bodies of domestic animals are today by the Green River. Then, 

 as the flesh was eaten by scavengers, the bones sank into the 

 sand and were entombed. Fortunately for us. many of those so 

 buried in this place were fossilized. 



Several great changes later took place, the whole area having, 

 among other things, been covered by a large sea or part of the 

 ocean for a long period. But eventually Ihe land rose again, and 

 erosion went to work on the now upended and exposed sections 

 of the deposits formed in the ancient delta. Again very fortu- 

 nately, a scientist happened to spot some of these fossilized bones 

 during a field trip in the year 189.? and recorded the fact. Fifteen 

 years later one Dr. Earl Douglass made an extended search whidT 

 finally brought him to the place of which we speak. 



Any citizen may now stand here and gaze upon the skeletons 

 of dinosaurs, both monstrous and minute, still embedded in the 

 sandstones of the ancient delta where they once lived and died. 

 Here the past stares you in the eye with a kind of knowing 

 twinkle, as if to say. "So you didn't really believe what you saw 

 in the museum, did you?"': and this can be most disturbing. You 

 begin to think of elephants and rhinoceroses and other unlikely- 

 looking creatures; and then, perhaps shrugging, you turn to 

 contemplation of the mighty dinosaur commonly called Bronlo- 

 saunis. and you realize that it is only a bit less likely. Then 

 other strange thoughts come to mind. 



These creatures, being reptiles, almost certainly laid eggs: 

 and. as far as we know from the few of these found, these were 

 comparatively very small. Did baby dinosaurs, whidi need not 

 have been much bigger than baby alligators when they first 

 popped out of their eggs, frisk about in the bright sun. or did 

 they dig themselves into the sand, or dart for water before one 

 of their larger cousins could snap them up? There is so much 

 more we would like to know about these fabulous creatures. 

 What for instance did they eat? What color were they? Did 

 some of them have flaming red heads, iridescent green bodies, 

 and bright blue tails, such as one lizard has today? Or were they 

 all just great drab-colored beasts like elephants and rhinos? The 

 very idea of baby dinosaurs is in some respects rather startling, 

 especially when you contemplate the remains of their vast 

 parents. But there were also little dinosaurs — quite apart from 

 baby big ones— that were not much bigger than chickens. One 

 (Laosaunisl that was first found here had an over-all length of 

 only two and a half feet, including its long, reptilian tail, and it 

 apparently rushed about on its hind legs just as the Basilisk 

 Lizard of Central America does today. But there are other even 

 more intimate things to be seen here. 



Prominent among these are considerable quantities of pebbles, 

 mostly about the size of your clenched fist, that are polished as if 

 by a jeweler. No known natural process can so polish a pebble, 

 for even the finest powdered dust leaves tiny scratches that 

 render the surface dull, while chemicals only etch it. These 

 stones were a mystery until a clutch of them were found occu- 

 pying the position once held by the stomach of a small fossil 

 reptile known as Proliguanadoii. From this discovery it became 

 apparent that many dinosaurs, like birds today, might have had 



Bristle-cove pines. It has been di^ some spec- 



imens of these gnarled, scrawny!' < in Califor- 



nia's White Mountains are about four thousand years old. 

 and thus among the oldest living trees. 



to swallow pebbles to aid in the grinding of coarse food in their 

 stomachs. And that would be the one place where such pebbles 

 could be so brightly polished. This seems to bring these impos- 

 sible-looking reptiles much closer, for it gives us one more point 

 to understand about them. The ultimate in getting to know the 

 dinosaurs was probably achieved by Roy Chapman Andrews in 

 bringing to light a dinosaur nest containing its eggs, some of 

 which had within them little dinosaurs about ready to hatch. 



The remains of some three hundred individual dinosaurs of 

 a dozen different species have now been extricated from the 

 sandstones of this place. Among these are more than two dozen 

 skeletons so complete that they have been mounted as a whole 

 in museums. In addition to dinosaurs, two kinds of crocodilians. 

 one a real pigmy, and a very ordinary-looking tortoise have 

 come from the same strata. Among the dinosaurs are the vast 

 brontosaur now known as Apatosaurus. its more slender relative 

 Diplodocus with its horsy head and strange, slender teeth: and 

 the long-necked Btirosaurus. two kinds of Cainariisaunis. and so 

 many remains of the fabulous Stegosaurus (which probably lived 

 on the drier uplands) that Ihe diggers became frankly bored with 

 them Of bipedal plant-eaters there are three: and there are two 

 flesh-eaters, one called Antrodemus. with a body about the size 

 of a mule and two-inch teeth with serrated cutting edges. 



