“That’s a whole lot of handle for a critter no bigger’n a fox!”
“‘Hippus’ means ‘horse,’ and ‘eo’ means ‘dawn,’” explained the boy, “so the Eohippus is the Dawn Horse, or the Dawn of the Horse.”
The cowboy rolled a cigarette.
“Which I’m admirin’ your lay-out a heap,” he said, “you’ve sure got a double cinch-strap on that horse stuff.”
“I ought to have,” said Perry, “it’s what I want to work at, though I haven’t had much chance in the field yet. Well,” he continued, “after a few hundred thousand years had gone by, Nature improved on the horse. She found she could make a better horse, if he was a little bigger, and that he could run quicker on three toes than on four. So in the next layer of rocks, which we call Oligocene, and which we can liken to the lower layer of the oak shavings, you’re apt to find skeletons of that three-toed horse, which is called Mesohippus, same as you’d find a knife-whittled oak horse in the lower layer of oak shavings.”
“And ‘Mesohippus’ means a ‘what-horse’?” queried Round-up Dick, remembering that ‘hippus’ was a ‘horse.’
“A middle-horse,” the boy answered, “halfway between the dawn horse and the modern horse.”
“Deal again,” said the cowboy.
“Another few hundred thousand years went by, a different series of rocks came and Nature again improved on the horse. She saw that he would be better if he were still larger, and swifter if only one toe reached the ground. So in the next layer, which corresponds, Dick, with the top part of the layer of oak shavings, we find a horse called the Protohippus. He had three toes, but only one of them touched the ground, the other two hung useless on either side.”
