lly, quite forgot the character of
his listeners, and laid his theories regarding the interchange of
mammalian life between America and Asia during the early Pleistocene
period, before Meeteetse Ed, Old Man Rulison, Tubbs, and others, in the
same language in which he would have argued moot questions with
colleagues engaged in similar research. The language of learning was as
natural to McArthur as the vernacular of the West was to Tubbs, and in
moments of excitement he lapsed into it as a foreigner does into his
native tongue under stress of feeling.

"I maintain," asserted McArthur, with a gesture of emphasis, "that the
Paleolithic man of Europe followed the mastodon to North America and here
remained."

Meeteetse Ed, whose cheeks were flushed, laid his hot hand upon his
forehead and declared plaintively as he blinked at McArthur:

"Pardner, I'm gittin' a headache from tryin' to see what you're talkin'
about."

"Air you sayin' anything a-tall," demanded Old Man Rulison, suspiciously,
"or air you joshin'?"

"Them's words all right," said Tubbs. "Onct I worked under a section boss
over on the Great Northern what talked words like them. He believed we
sprung up from tuds and lizards--and the likes o' that. Yes, he did--on
the square."

"There are many believers in the theory of evolution," observed McArthur.

"That's it--that's the word. That's what he was." Then, in the tone of one
who hands out a clincher, Tubbs demanded: "Look here, Doc, if that's so
why ain't all these ponds and cricks around here a-hatchin' out children?"

"Guess that'll hold him for a minute," Meeteetse Ed whispered to his
neighbor.

But instead of being covered with confusion by this seemingly unanswerable
argument, McArthur gazed at Tubbs in genuine pity.

"Let me consider how I can make it quite clear to you. Perhaps," he said
thoughtfully, "I cannot do better than to give you Herbert Spencer's
definition. Spencer defines evolution, as nearly as I can remember his
exact words, as an integration of matter and concomita, dissipation of
motion; during which the matter passes from an indefinite heterogeneity to
a definite, incoherent heterogeneity, and during which the retained motion
undergoes a parallel transformation. Materialistic, agnostic, and theistic
evolution----"

Meeteetse Ed fell off his chair in a mock faint and crashed to the floor.

Susie, who had entered, saw McArthur's embarrassment, and refused to join
in the shout of