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Rh because we do not know the period of life in the female. If, however, we estimate it at thirteen years, which seems to be a conservative figure, the animal would have ten years of breeding life. Then, from old age alone, ten per cent of the adult breeding females must die annually. This leaves a net gain of six and two thirds per cent with accidental factors unaccounted for. The killing of females which does not produce actual diminution must come well within this margin of six and two thirds per cent. It only remains to be stated that the pelagic catch of 1897, which was the smallest on record since 1884, exceeded fourteen per cent.

14. While, whether from a consideration of the birth rate or from an inspection of the visible effects, it is manifest that the take of females in recent years has been so far in excess of the natural increment as to had to the reduction of the herd in the degree related above, yet the ratio of the pelagic catch of one year to that of the following has fallen off more rapidly than the ratio of the breeding herd of one year to the breeding herd of the next.

This paragraph corrects possible erroneous implications which might be drawn from the truism in the preceding paragraph. A certain number of females may be taken, etc., but so many in excess of the safety limit have been taken that the herd has been reduced “in the degree related above”—that is, for 1896-97, nine to twelve per cent, and for 1884-'97, fifty to eighty per cent.

Dr. Mendenhall said: “It will be impossible to know absolutely which group of scientific experts was right (in 1892) in regard to pelagic sealing.” The admission made in this paragraph, taken together with other admissions made in paragraphs 11 and 12, effectually disproves this prediction. It ought to be a source of gratification to Dr. Mendenhall and to his colleague, Dr. Merriam, to find it thus clearly proved that they were right and their British associates wrong.

The final clause is here again a diplomatic concession to take the sting out of the real admission. The rapid fall in the pelagic catch as compared with the more even decline of the breeding herd is a natural phenomenon. Pelagic sealing not only destroys the herd, but it is necessarily self-destructive because it preys upon its own capital. The more successful it is the sooner it must cease. With the decline of the herd it is itself declining, and the rapidity of its fall proves the nearness of the end. For the years since 1894 the pelagic catch has been 61,000, 56,000, 43,000, and 25,000 respectively. It is a significant fact that in four years, under regulations which permit the pelagic sealer to take all he can get, the product of his industry has fallen to less than one half.

15. In this greater reduction of the pelagic catch, compared with the gradual decrease of the herd, there is a tendency toward equilibrium, or