d bruises,
followed their gaze to the excavation.

"We are pulling out ten million years," answered Professor Wright,
slowly, in rather solemn tones. "Ten million years! We are pulling
out a creature that walked the earth ten million years ago!"

There was a gasp from the listening cowboys, and Babe murmured:

"His brain sure is cracked!"

"Ten million years!" murmured Mr. Merkel. "But what has that to do
with rustling Diamond X cattle?"

Before anyone could answer, there was some movement at the far end of
the valley camp, and into it came rushing several more steers bearing
the Merkel brand. They were being driven by several Mexican Greasers,
who seemed very much surprised at the scene that met their gaze. In
vain did Del Pinzo attempt to signal them to retreat.

It was too late. On they came, and with yells the Diamond X cowboys
rushed for these latest arrivals.

"More rustling!" cried Bud. "We've caught 'em right at their game!"

"Go get 'em, boys!" commanded his father.

And in a few minutes, after the exchange of a few shots, the other
Mexicans were captured, with the exception of one or two at the rear of
the bunch of steers. They managed to ride off in the confusion.

"Oh, boy!" murmured Bud, as he threw his hat up in the air. "This is
great! Even Zip Foster couldn't beat this!"

"He'll not get the chance, I guess!" murmured Nort, laughing.

"Looks like we'd corraled the whole bunch," said Slim. "Now let's take
a look at this ten million year old creature the professors seem to
have bagged."

The prisoners were now secured and the boy ranchers, with Bud's father
and his cowboys, drew near the great hole in the ground--the hole over
which leaned an improvised derrick. From this derrick ran a long rope,
rigged over pulleys, and it was to the pulling end of this cable that
the Diamond X steers were hitched. The lifting end of the rope
extended down into the excavation.

"Just what sort of game is going on here?" demanded Mr. Merkel, and But
knew when his father spoke in this tone that there was likely to be
trouble for some one. "What does it all mean?"

"The explanation is a long one," began Professor Wright, "but----"

"It doesn't take very long to size up that you've been rustling our
cattle!" said Slim, sharply.

"Rustling!" murmured the professor. "Rustling? Oh, I see, a western
term for borrowing."

"_Borrowing_! Oh, Zip Foster!" murmured Bud, but his father motioned
fo