In all such cases- -and many could be given — if the age for reproduction were retarded, the character of the species, at least in its adult state, would be modified; nor is it improbable that the previous and earlier stages of development would in some cases be hurried through and finally lost. Whether species have often or ever been modified through this comparatively sudden mode of transition, I can form no opinion; but if this has occurred, it is probable that the differences between the young and the mature, and between the mature and the old, were primordially acquired by graduated steps.

6. Special Difficulties Of The Theory Of Natural Selection

Although we must be extremely cautious in concluding that any organ could not have been produced by successive, small, transitional