spawn, placed it in his pond to hatch. Again he was successful. The eggs at the proper time disclosed their fish; these in a short time were seen to be unmistakeable parr: after a period becoming smelts, and so growing through all the grilse stages into undoubted salmon. Curiously enough, another practical man had engaged in similar experiments, almost simultaneously with Mr. Shaw. Mr. Young, of Invershin, manager of fisheries to the Duke of Sutherland, by a similar process had also convinced himself that the parr was the young of the salmon. The experiments of these gentlemen, however, originated a new branch of controversy. Granting that the parr had been proved to be the young of Salmo Salar, the question now was—At what time did it become a smelt? In one year, said Mr. Shaw. “Nay,” said Mr. Young, “it is two years before the change takes place.” Both gentlemen have been found, by means of the experiments at Stormontfield, to be right. One-half of the parr of any year’s hatching undergo their metamorphosis into smelts and depart for the sea at the end of twelve months from the date of their being hatched; the other moiety does not depart for the sea till a space of two years has elapsed!
This curious anomaly in the growth of the salmon has never been explained. Up till the experiments of Shaw and Young, the smelt was always considered to be the fry of the salmon in its most infantile stage—in fact, the fishmonger who asserted that the spawn of that valuable fish was hatched in forty-eight hours, was not worse informed than the men who supposed that the fish within a few days of its breaking the shell grew to be a smelt six or seven inches Jong and of corresponding girth. It is impossible to account for the young fish being thus divided—one half changing the one year, and the other half in the year following. Before these various experiments were made, no one, of course, had noticed this remarkable circumstance in the history of the salmon. The parr being thought a distinct fish, attention was centred in the smelt, and, as has been stated, it was thought to be the young salmon grown magically large within a few weeks of its birth. The little fry, the parr, are on most salmon rivers captured in thousands. At some places they used to be advertised, just like whitebait, as a rare fish delicacy, nobody taking into account that in every female parr which they placed in their fryingpan they were killing a countless number of future salmon. As a matter of course, a considerable percentage of fish are still spared (out of the large number of eggs which are annually hatched) to become smelts; these, again, have their own particular enemies. On their way to the sea they become the prey of innumerable anglers, and on their arrival at the salt water they are waited upon by a horde of sea cannibals, who straightway begin to feast upon them, decimating the arriving shoals with the greatest possible industry. A twenty-pound female salmon will yield twenty thousand eggs, but about half of that number only will come to life; as many of them will waste for want of fructification; others will be devoured by the yellow trout or other fishes, and many more by the wild fowl. Again, a few thousands of the parr will be lost long before they become smelts; and these latter will, from various causes, be reduced in the river and sea to about a third of their original number; these again changed into grilse, will gradually be seized upon by fishermen and anglers, till only a very few of the original fish are left to become salmon and perpetuate their kind.
Before discussing one or two other interesting features of salmon-growth, it may be as well to allude to a dispute which is yet going on, very similar to the parr controversy. It has already been shaped into a pertinent question, and “What is a sprat?” is ever and anon being asked by both the ignorant and the learned. Well, as in the case of the parr, and the two cases are very similar, there are people who believe a sprat to be just a sprat, and nothing more. But there are others, equally learned, who say that a sprat is a young herring. There has been some fighting over these two propositions—the sprat-and-nothing-but-a-sprat men assert that their fish is a totally distinct individual, and neither the son nor the daughter of old Clupea harengus. “The sprat has a different shape.” “The sprat has a serrated abdomen.” “The sprat has a larger number of vertebrata.” “The sprat is very oily.” “The sprat has its fins differently placed from the herring.” “The sprat is—in fact, the sprat is a distinct fish, and that’s all about it,” say the “old fogies.” “All the differences you mention,” reply the other side, “are of no consequence, the serrated belly is a mere provision for growth; the oiliness of the sprat cannot be greater than that of the pilchard; the fins will be adjusted as the animal grows, and so will the shape; depend upon it we are correct, and that sprats are young herring.”
So the dispute stands for the present, and there is no pond for breeding herring where the question might be solved. Some of the objectors to the young of the herring being thought sprats, say that they have specimens with spawn in them, and that were they not a separate fish it could not be charged with spawn. But this argument must fail, because plenty of young parr have been taken in the Tay and elsewhere with spawn. Indeed, at the Stormontfield ponds the milt from a male parr was used to impregnate the ova of a full-grown female salmon! It is certain, too, that as a general rule the sprat is not found with either roe or milt developed in it; it is likewise certain that sprats and young herring are found in the same shoals, they are sold indiscriminately as sprats, and millions of them are annually consumed in London and elsewhere. After the dogmatic way in which the parr question was argued, it would be unsafe to assert that the sprat may not some day be proved to be the young of the herring (Clupea harengus), or of the pilchard (Clupea pilchardus). The French, we believe, are taking steps to solve the question by means of their large salt-water aquarium. M. Coste, who is great in all questions connected with pisciculture, will add another laurel to his brows if he succeed in determining the question of What is a sprat?
A case in point as regards fish-growth, although the crustaceans are not exactly fish, has been