THE GREAT CEMETERY IN COLORADO. 471 



in the animate scale ; while the star of the resplendent ammonite 

 went down in utter death. And there must have been peculiar condi- 

 tions of both land and sea, in that Cretaceous day, or those strange 

 reptiles of Brobdingnagian altitude could not walk on the land ; nor 

 could their aquatic congeners of cetacean bulk, the huge sea-reptiles, 

 move in their briny homes ; so with the Ammonites, and the great 

 selachian fishes. But these — the beauties and the monsters — all died, 

 for there came in new conditions of the land, the sea, and the air. 



And with these new conditions came the Eocene age, or dawn of 

 the Tertiary epoch of Earth's lifetime. So decided was this physical 

 change, that all things were ready for its reception of a new race of 

 living creatures. The very surface was newly and lavishly garnished, 

 like a table awaiting the expected guests. And the atmosphere had a 

 balmier vigor, a sort of climatal ripeness, like the aroma of an autum- 

 nal orchard whose fruit has matured. Now came the true grasses, 

 and the grains ; and the Rosaceae plants with the strawberry, black- 

 berry, apple, cherry, and plum, etc. And Nature's guests arrived, 

 and entered upon the enjoyment of an unrestrained existence in her 

 grand domain. And they were welcome guests ; for leading the train 

 came the (as yet) noblest of her begettings, beings of true mammalian 

 rank. They were of new forms and new appetencies. Some were 

 petite in size, and some were of more than leviathan proportions, and 

 many were bizarre in form ; and all were diverse from every thing 

 that had lived before, or that should ever come after. And so each in 

 its own way, as disposition or convenience prompted, enjoyed life. 

 Some preferred the banks of the great rivers, others the grassy meads 

 of the green valleys, and others the sides of the densely-wooded hills. 

 And the timid rodents hid themselves in their burrows at the roar of 

 the carnivores, while both were startled by the beastly bellowing of 

 the great terrestrial behemoths. And these beings, at least some of 

 them, have left their relics in the far West, in places where, until 

 lately, only the red-man had trod. 



The geological age just mentioned is called the Tertiary. It was 

 for the first time with true significance sectioned off by Sir Charles 

 Lyell. This learned geologist noticed that this age opened with ani- 

 mal life more like that of the present than any thing that had been 

 before, and that in respect to the molluscs there were many forms 

 identical with existing shells ; and he noticed that, as we ascended in 

 this age, the percentage of forms thus similar very rapidly increased. 

 He, therefore, named the bottom section the Eocene, meaning the 

 dawn ; and the middle section the Miocene, meaning less of its dawn, 

 that is, farther on in the day; and the highest section he called the Pli- 

 ocene, meaning still more advanced. To these has been added 

 another, namely, the Pleistocene. 



There are three American names which, in respect to the most 

 recent results in vertebrate paleontology, deservedly stand as its 



