EMBRYOLOGY AND EVOLUTION
and its main course; the latter determines which of these possibilities are realized and modifies more or less the course of development.
Entirely similar causes are at work in the evolution of races or species. With true insight Charles Darwin wrote, many years ago: “Although every variation is either directly or indirectly caused by some change in the surrounding conditions, we must never forget that the nature of the organization which is acted on essentially governs the result.” Whether these variations are first wrought in mature organisms and then transferred in some unknown way to the germ cells, as Lamarckians assert, or whether they first appear in the germ cells, as Weismann and his followers maintain, is a secondary, although important, consideration, into which we will not enter here. In conclusion it may be confidently asserted that the causes or factors of the evolution of species and of the development of an individual are fundamentally the same.
Development, Evolution, and Religion
What bearings do these scientific evidences as to the origin of individuals and species have on religious faith? It might satisfy our pride to believe that every human being sprang into existence fully formed and armed, like Minerva, from the brain of Jove, but however pleasing such a belief might be it could not be held by sane and enlightened people. We know well that every human being, even the greatest that ever trod the earth, was once a baby, an embryo, a germ cell, and this knowledge has not destroyed our belief in the dignity of man nor in the existence of God.
It pleases many persons to believe that the first man sprang into existence fully formed and perfectly endowed, coming directly from the hand of God by an act of super-
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