Determinate evolution

Reviews the 2 current doctrines of heredity, Natural Selection and use-inheritance or Lamarckism, and discusses their inherent criticisms. The author suggests that there is another influence at work: Organic Selection. This principle states that acquired characters, or modifications, or individual adaptations, i.e., Accommodations, while not directly inherited, are yet influential in determining the course of evolution indirectly. For such modifications and accommodations keep certain animals alive, in this way screen the variations which they represent from the action of natural selection, and so allow new variations in the same directions to arise in the next and following generations; while variations in other directions are not thus kept alive and so are lost. The species will therefore make progress in the same directions as those first marked out by the acquired modifications, and will gradually "pick up," by congenital variation, the same characters which were at first only individually acquired. This principle comes to mediate to a considerable degree between the two rival theories, since it goes far to meet the objections to both of them.