The Past 5 



of an entirely new genus and species of insect, which was called 

 Petropteron mirandum, — the admirable wing in the rock. The 

 insect of course belonging to the land, had by some misfortune got 

 drowned in the sea, and buried in what was then soft mud. Prob- 

 ably a lifetime of searching in the brickyard would not produce 

 another like it. Such are the chances of paleontology. In England 

 the remains of a remarkable dragon-fly were found inside an 

 ammonite, which is a marine shell long ago extinct. The ammonite 

 itself had been washed out of the original rock, and redeposited 

 in the boulder clay, which belongs to very recent geologic times. 

 Thus we know that the ammonite first died, and then the dragon- 

 fly, falling into the sea, was by some accident washed in to the 

 dead shell, with enough mud to fill it up. The whole became 

 fossilized, and the fossil, many millions of years later, was washed 

 out of the deposit, and into a new one. Here it was eventually 

 found by man, who by employing the brain which had in the mean- 

 while evolved, could tell the story as it must have occurred. 



In the Loup Fork (Tertiary) beds of Kansas, bones of large 

 vertebrates are found, but the conditions were not favorable for 

 the preservation of plant remains. But inside a skull some hard 

 seeds happened to lodge, and thus were preserved. They proved 

 to be very similar to those of our modern"Snow-on-the-Mountain , 

 and were named Tithymalus willistoni, after the eminent natural- 

 ist who first called attention to them.* 



THE FOSSILS OF THE OIL SHALES 



Leaving the train at De Beque, in Mesa County, and follow- 

 ing Roan Creek toward its source, we pass up deep valleys, between 

 high mesas which rise some two thousand feet on either side. On 

 the top is a growth of sage brush, with occasional stands of Douglas 

 spruce, while the depressions and draws, supporting more luxuriant 

 vegetation, are the home of the glorious white columbine, a variety 

 of the state flower of Colorado. So distinctive is this flower, 

 appearing like stars against the green of the shrubbery, that it 



*Samuel Wendell Williston, whose father had never learned to read or write, found hi* 

 opportunity in the Kansas Agricultural College, under the stimulation of a teacher of science. 

 Professor Mudge. Under Mudge he became a collector of fossils, at first for sport. In the 

 course of a long and active life, he became one of the greatest living authorities on fossil verte- 

 brates, and also the leading student of American flies (Diptera). He served as professor first 

 in Kansas, later in the University of Chicago, communicating his enthusiasm to many disciples, 

 who are still at work. 



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