THE REIGN OF MAMMALS. 209 



has been noticed. The fauna of the period was eminently 

 characterized by the presence of pachyderms and rumi- 

 nants, and this in the same age when Europe was popula- 

 ted by a large admixture of the higher carnivores. 



I said this valley of death has the appearance of a sub- 

 sidence in the wide extended plain. The suggestion is so 

 natural that one almost irresistibly regards it as a vast 

 sunken grave, where the slain of a geological convulsion 

 have been gathered together and decently entombed, and 

 the earth has at last settled down upon their crumbling 

 remains. A better judgment, however, discovers the val- 

 ley to be the work of excavating waters. Gigantic as the 

 scale of such digging must appear, the geologist is ac- 

 quainted with other examples immeasurably more sub- 

 lime. They belong to the phenomena of the Post-Tertiary 

 Age. These towers, then, have not been built up, but have 

 been left in relief, like the figures on the sculptor's marble. 

 Torrents of rain have wielded the instruments that have 

 fashioned the Titanic architecture. 



From this Golgotha, if we wend our way northward 

 some hundreds of miles nearer the sources of the Missouri, 

 we find ourselves standing again upon the deposits of a 

 vast inland sea — a sea which was still remaining when the 

 Bad Lands were drained. Around the shores of this far 

 northern basin of water lived, in a later age, the rhinoce- 

 ros, the elephant, the mastodon, the camel, the horse, the 

 beaver, the wild-cat, the wolf, the land tortoise, and other 

 genera of quadrupeds now extinct. In this lake the Mis- 

 souri took its rise, while the Yellowstone and other rivers 

 poured into it the drainage of the region beyond, and trans- 

 ported the relics of then existing races, with other sedi- 

 ments, to the burial-place from which they have recently 

 been exhumed. 



It gives me great pleasure to make known to the reader 



