The tracks, blurred by the drifting snow on the forest floor, made no sense. Appearing from nowhere and going nowhere, the unidentified creature's imprints circled back on themselves, causing the human hiker to lose the trail in the tracks of his own boots.

Like all good mysteries, it teased the outdoor detective into a further reading of the clues. In the center of the track-inscribed circle stood a white pine tree, around the base of which the snow was much trampled.

On the lee of the tree the tracks became clear: five toes, a blank space for the arch and a hollow for the heel, as if some crazy fool had been dancing barefoot in the snow. Only the tracks were wider than human footprints.

Long strips of peeled bark on the white pine trunk completed the puzzle.It was a rubbing tree, and the maker of the claw marks on the tree and of the barefoot tracks in the snow was an eastern black bear, whose winter den of quasihibernation must have been close indeed.

Without the aid of recently fallen snow, the hiker probably would have noticed none of this. For lost in the centuries between Stone Age hunting and cellophane-wrapped meat was man's ability to scent the trails of other animals.

Here, though the shape, size and pattern of tracks on the tabula rasa of snow tell an easy-to-read story of comings and goings, nocturnal and life-and-death excursions normally invisible to modern man.

A few yards from the rubbing tree the hiker spotted another series of tracks, this time a meandering line of cloven-footed prints. Dead on top of these tracks were sets of four small holes in the snow. The hiker struck the trail.

The cloven prints unmistakably were left by a whitetail deer, the only wild animal in these parts with hoofs. The superimposed hollows in the snow, no closer examination, were recognized as paw prints, apparently belonging to a dog, domestic or feral, which was on the trail of the deer.

The direction of travel was equally easy to figure; the deer's dewclaws point backward and the dog's toes, of course forward. The dog was far behind in chase, for there was no evidence of panic in the deer's tread.

Had it been galloping, the deer's hind tracks (indicated by the dewclaws spaced farther from their respective hoofs than in the front feet) would have been ahead.

The trail was not fresh, but neither was it old. The deer's droppings ("scats" in tracking parlance) of dark, round pellets, readily visible on top of the snow, were frozen solid. But the tracks had broken the snow's ice glaze from the previous night, and it was not yet noon.

Still, the deer's tracks had been too old for the dog, which after about a half-mile evidently had caught wind of something more interesting and had broken off the deer trail. The hiker decided to stick with the dog, tracking the tracker.

The second-hand tracker soon realized, however, that it hadn't been at all. The paw prints were much too straight on line. DOgs, with wide upper torsos that push the front legs to the side, leave zigzag paw patterns.

Moreover, the trail led along the top of slippery trunks of fallen trees and over rock ledges that most dogs, when given alternative routes would avoid.

It was a fox, whose individual paw prints are almost indistinguishable from a small dog's.

Within another half-mile the fox's trot had turned into a run . . . and then a long, unbroken space of snow, over which the fox must have leapt. Toward what, the hiker could not exactly tell, for there were not other tracks to be seen.

From the very lack of tracks, however, it was obvious the fox' prey had been small, too light to leave a record on the snow's hard crust - probably a squirrel or half-frozen bird.

What ever it had been, it was now in the fox' stomach, for there were no drops of blood on the virgin snow, and the fox' tracks leading away from the kill seemed, at least in the hiker's imagination, heavier.

Before the day was over the hiker - armed with Petersons "Field Guide" for quick decoding - would read the snow as clearly as the morning newspaper. He would actually see what he had previously experienced only vicariously through the ever-sniffing nose of his pet dog.

Now, although he hadn't been there when the raccoon had left hand-like footprints during its nocturnal wanderings or when the rabbits had left sets of dimples in the snow searching for stalks to chew, he knew what he could never witness, knew that these events had happened.

In fact, if he had been there, his presence would have excluded the happening.