=Answer=.--It may be well to note that this apparent permanence is true of _races_ of men as well as of _species_ of animals and plants. But the very men who insist on permanence of species are equally insistent on the variability of varieties and races. The objection, therefore, proves too much. We shall not insist on this, however, because as derivationists we regard races as naught else than commencing species, and therefore subject to the same laws. We are not striving for triumph in debate, but only for truth. The true answer will, we believe, be found among the following suggestions: 1. Three thousand years seems a long time in human history, but in geological history it is but a day. This, the usual answer, is no doubt a true one, but hardly, we think, sufficient. When we remember the enormous change which has taken place in faunas and floras since the end of the Tertiary, if change still continues at the same rate, surely it ought to be distinctly perceptible in three thousand years. 2. But we must remember that such changes are usually more or less paroxysmal; not, indeed, so sudden as to break the continuity of life, but far more rapid at some times than at others. The last critical or revolutionary period of rapid change was the Glacial epoch. Since that time--i. e., during the human period--a new equilibrium has been established, and the changes in organic forms have been very slow. 3. Remember, again, that in evolution _all_ species do not change. On the contrary, most become rigid, and either remain unchanged, almost indefinitely, or else die out and leave no descendants. Only the more plastic forms change into other species, but usually into several other species, and thus the number of forms may be undiminished, even though the larger number of old forms leave no descendants. It is true, therefore, of this as well as of other epochs, that the greater number of species are permanent.