nce you try them.

"There are other names of animals in everyday use that would 'stump' us
if we stopped to think of them, but we don't. We rattle off mammoth,
rhinoceros, giraffe and boa constrictor easily."

"Yes, they sound easy enough," argued Bud.

"Well, all you need to do is to apply to the extinct monsters the same
principle of pronunciation that you use in saying hippopotamus, and you
have done the trick," went on Professor Wright. "In fact, it is all
rather simple."

"Simple," murmured Dick. "Bront--bront--brontotherium!"

"Take it by degrees," advised Professor Wright, "and remember that
generally these names are made up of one or two or even more Greek or
Latin words. Sometimes a Greek and Latin word is combined, but that
really is not scientific.

"Now, in the case of the brontotherium, we have two Greek words which
excellently describe the animal whose bones I am after. That is the
description fits, as nearly as anything can to something we have never
seen.

"There is a Greek word--_bronte_ it is pronounced in English, and it
means, in a sense, thunder. Another Greek word is _therion_, which
means wild beast.

"Then bronto--bronto--therion must mean--thunder beast!" cried Dick,
rather proud that he had thus pieced together some information.

"That's it!" announced Professor Wright. "You see how easy it is.
Change _therion_ to _therium_ and you have it."

"But why did they call it a thunder beast?" Bud wanted to know.

"There doesn't seem much sense in that," admitted the scientist, "until
you stop to think that paleontologists adopted the word 'thunder' as
meaning something large and monstrous, as thunder is the loudest noise
in the world."

"Not so bad, after all," was Dick's admission.

"I'm glad to hear you say so," commented the professor. "To go a bit
farther, take the word Dinosaur."

"I know the last end of it means a big lizard," put in Bud.

"Yes, and the front of it--the prefix _dino_, means the same thing that
_bronto_ signifies--something large, terrible and fear-inspiring. Dino
is a form of word taken from the Greek, _deinos_ meaning terrible and
mighty, from its root _deos_, which means fear.

"So those who first discovered these great bones, having reconstructed
the animals whose skeletons they formed, gave them scientific names
best fitted to describe them. Can you think of anything more aptly
descriptive than 'thunder-lizard,' to indicate a beast shaped like t