All this seemed to be too much for Skeeter, who stretched out his neck till his muzzle was in a line therewith, literally shed tears, opened his mouth, distended his nostrils, and with ears quivering, emitted the most startling sound ever heard. It was not a neigh like his mother would have given, nor a bray such as his father would have uttered, but a hoarse yell made up of the most discordant elements of both, and it was no wonder that the doctor’s voice was drowned.

“Be quiet, you brute!” he cried angrily, making a pretence of kicking it in the pack; and then he stared in wonder, for it seemed as if a fresh misfortune had affected one member of the expedition in a peculiar way. That member was Chris, who suddenly dropped his hold of Skeeter’s rein, and with his face horribly distorted, began to roll about in his saddle.

“Oh, Griggs!” he gasped. “Ned! Somebody! Hold me on.”

“What is it, boy?” cried the doctor—“Bitten?”

“N–n–n–n–no, father,” he panted. And then, “Oh dear! Oh dear! I—I—I—I—I can’t help it. I—”

There were other words, but they were confused and strange; but though they did not convey in words the meaning of the seizure, they pointed out what was the matter. For it became evident that Chris was laughing wildly—madly—hysterically, and to such an extent that he had lost all control of himself, and had hard work to keep in the saddle.

To make matters worse, the mirth proved contagious to such an extent that Griggs sat looking at him, then at the mules, and back again, with his mouth expanding into a broad grin, while Ned slid off his mustang quietly, held on to the rein, and then lay down in the sand, to laugh in the same uncontrolled fashion.

“Well,” cried Bourne angrily, “this is a nice way to treat our misfortunes!”

“I—I—I can’t help it, father,” panted Ned, and he laughed more than ever, while Wilton’s lips as he sat looking on began to quiver and then widen out.

“Here, stop it, you two,” he growled at last. “Come and help collect the things.”