Slowly the great herd moved southward. The shaggy beasts were moving down from the howling winds and the sharp, biting snows into the sunny southlands, where the heat was pleasant and the long days could be used for browsing. There were thousands and thousands of buffalo, moving easily and steadily along the mile-wide trail, behind the short, sharp horns of the huge old bull leader.

At the flank of the moving mass ran young Greysides. His legs were strong with muscle, and the mighty hump above his shoulders was already bristling with curly brown hairs. He was but a few months over one year old. Yet with the quick maturity of all wild things, his body was already big and strong. Gone were the wobbly legs and the scrawny neck. Now his mane was much like that of the old bull leader, a dark mat of bristly hair growing all around his curving horns.

In another few years, Greysides would be ready to challenge the bull leader for the leadership of the mighty herd. Now he was just a young buffalo with strength - and not much wisdom.

For Greysides like to explore. Not the middle of the herd for him, rubbing sides and clicking horns with other buffalo all around him. He chose the flank, where his alert brown eyes could stare out wonderingly at the strange new world unfolding as the herd southered steadily. He saw a snarling bobcat running smoothly away from the thundering thousands; saw an Indian sitting on his pony on a distant bluff, watching the herd approach; saw a slinking form that he knew instinctively to be an enemy, though Greysides had never seen a wolf before.

And then - in the midst of that placid, steady running - a screaming ululation lifted the hackles at the base of Greysides' hump. The young buffalo snorted and increased his pace. A Cheyenne arrow thudded into the buffalo ahead of him. A feathered lance drove deep into another.

The herd was splitting, being divided by screaming, yelling Indians who waved blankets and lances while others charged in and out of the herd, bowstrings twanging.

Perhaps it was that same wanderlust in his soul that made him choose the flank of the herd that now drove Greysides upward from the flat stretch of sageland. He ran furiously, his short legs pistoning with a fury that made them blur with movement. Head down, eyes red with rage, Greysides ran on and on.

The yelling and the sharp arrows that bit and hurt were far behind, now. Greysides snorted and nodded his great head. There was an ache in his right shoulder, and another in his flank. Greysides knew that the things on horses had made those aches by shooting little thin pieces of wood at him. He was vaguely surprised that anything so small could hurt so much: but being a wild thing Greysides was used to pain.

The young buffalo lurched against an outcropping of rock. The rubbing of his thick skin against the stone drove one shaft free of his shoulder, and snapped off the other.

Greysides had lost much blood. He was weak. One of the arrows had gone deep. He trotted on, up along a winding trail between two sharp walls of a canyon path. Far behind and below him the Cheyennes were still riding with the fleeing herd, but Greysides had forgotten that. He moved onward, past shale-strewn canyon floors, and out across fields rich with bluebells.

For hours, Greysides ran. Occasionally he browsed, cropping at the grass. Once he threw up his head warily, sniffing at the breeze that swept by him. There was a man-smell in the air!

Greysides thundered off, shaking the earth with his running. When the fierce excitement of his heart lessened, he stepped forward and stared down a a white man clad in buckskin leggings and a fur jacket who was patiently sliding a clamp-trap under some leaves and brush. Greysides watched him warily, not knowing the purpose of the trap, but realizing dimly within him that man was a dangerous animal.

Greysides snorted softly. He was weak and tired. He had lost much blood: too much for safety, he knew. The young buffalo turned his head - and froze rigidly.

Standing a hundred feet away, big and tawny in the fading daylight, was a wolf It was the same wolf Greysides and seen from the flank of the herd, but Greysides did not know that. The wolf stared at Greysides steadily, and then his mouth opened and his red tongue run out, and it seemed that he was laughing at Greysides.

Kipi-ti, the wolf, was a smart hunter. For years he had roamed the slopes of the Tetons, and many a hare and squirrel had fallen to his crunching fangs. Once, long ago, Kipi-ti had tasted buffalo meat. But it had been so long ago, Kipi-ti could not remember its taste; could remember nothing except that it was - good.

Kipi-ti was hungry. The buffalo bull before him was young, not yet as strong and as formidable as he would be someday, if he lived. And the young buffalo bled from flank and shoulder. He was weak. Kipi-ti had followed him for a long time, and Kipi-ti was wise in such things. All he needed to do was trail the young bull, make him run and run, until those short legs buckled, until that hair-protected neck swung weakly...

It would be then that his white fangs would flash! He would leap and cut at those trembling legs, ham-stringing the young bull by severing the tendons of his legs with his teeth. Then, crippled and falling because of his ruined legs, the buffalo would lie helplessly as Kipi-ti drove in for the kill.

Greysides grunted through his nostrils as he swung away from the rank wolf-smell. Head down, he raced down the sloping ledge of rock from which he had seen the man-thing set his traps. He tore away from the oncoming wolf, digging huge chunks of dirt with his sharp hooves.

It was close to sundown when Greysides started his run. The lowering red sun sank further and further, and still the young buffalo ran. Now a faint dusk descended over the land, like a thin veil that presaged the approach of night's blackness.

Kipi-ti ran easily, always fifty to sixty feet behind the bull. He was fresh. Besides, the tired lurching of the young buffalo made his own body seem fresh and eager.

Finally, Greysides stopped running. He turned and lowered his head and his rage-red eyes sought out the big wolf. Greysides lowered his shaggy head so that the new moonlight caught at the curving white horns uprearing from his massive skull. Horns down, Greysides charged!

Kipi-ti leaped aside just as that huge head swiped at his flanks. It was close. The young bull was quicker than Kipi-ti had thought! But the canny old wolf knew Greysides could not last much longer. Soon now, he would stand with his legs spread, his head lowered, his breath misting into silvery smoke puffed like gunshots from his flaring nostrils.

Greysides charged a second time. Either he was slower, or old Kipi-ti was more respectful, for he missed him by a foot. Greysides went thundering on, not stopping to turn and charge again. His red eyes told him that the wolf was far more agile than he. His only chance was to outrun him.

Again the young buffalo slammed his hooves at the ground in a steady run. Behind him, racing swiftly but easily, came Kipi-ti, red tongue lolling out as if laughing at Greysides' attempts to escape.

He was near exhaustion, now. He staggered and lurched crazily. But Greysides was moving past the stone ledge, beneath it, and he knew the wolf was following...

Tiiiingg!

That was the clamp-trap snapping shut on Kipi-ti's forefoot! The night air shivered to the raging snarl in the old wolf's throat. Greysides swung about and stood, head lowered, nostrils belching misty air. He was exhausted. He could not have run any more. But the memory of the man-thin and of the thing he had hidden in the brush had been strong. And Greysides had seen the fur coats such as Kipi-ti wore in the bag at the man's side. It had been a gamble, but Greysides had won. He would grow strong again, and overtake the herd.

Greysides moved off through the night, while behind him Kipi-ti crouched low and bit at the trap, and awaited the coming of morning - and man...

THE END