When the time for this migration approaches, the parr, which has been steadily growing plumper, undergoes another curious change. The carmine spots fade out, and the soft skin becomes covered with silvery scales which obscure the dark bars on the sides, although the scales can easily be rubbed away. At this period the young salmon is called a smolt, and the smolt was also a riddle to wise men, for a long time. It was thought that smolts which went down to the sea weighing three or four ounces, returned to the rivers in three months weighing six or eight pounds. Of course, such a gain as this was a very wonderful, indeed an unequaled performance, like the “swellin’ wisibly” of the Fat Boy in the “Pickwick Papers.” It is now believed, however, that the smolt requires a year or fifteen months at sea for this great gain in weight. Then he returns to his native river, no longer an insignificant smolt, but a vigorous, beautiful grilse. The grilse is more slender than the salmon, the tail more forked, the scales more easily removed, and the top of the head and of the fins is not quite so black. But the grilse’s sheeny, satiny sides are even more brilliant than the salmon’s, and it is more playful and active, although its strength is less enduring. After the grilse has frolicked its way to the head of the river and spawned, it returns to the sea. When it visits the river again, the next year, it has become a full-grown salmon. These are the successive stages of the salmon’s life. But, even in the last and most familiar stage, the salmon’s habits are not fully understood. It is known that both young and old salmon, after descending a river, remain for a time in the brackish water at the river’s mouth, where they get rid of fresh-water parasites which have become attached to their sides, and where their scales are hardened by a diet of small fish; but where in the sea salmon go, no one knows. After leaving the coast, they disappear. They have been found in very deep water hundreds of miles from any salmon river; but their marine feeding-grounds are still undiscovered. In the spring they suddenly re-appear at the mouths of rivers, where they linger to free themselves from marine parasites. While in salt water, they will never jump at a fly; but as soon as they enter the fresh water of the Canadian rivers, in June, the waiting Indians and fishermen see them rising freely out of the water. Yet much of this leaping is plainly only for sport, and many people claim that salmon actually eat nothing at all during the time that they are going up rivers. These rivers offer a succession of pools and rapids. In almost every pool, during the day-time in summer, there are salmon resting from the labor of stemming the current. It is said that at night they are often to be found on the bars in the shallow rapids above the pools. If the water is low they ascend very slowly, but any rise in the river stimulates them into a rapid movement upward. When they