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Death is due to differentiation and not to a “running down” of the organism.

Lillie, F. R.

1909. The Theory of Individual Development. Pop. Sci. Mo., Vol. LXXV, pp. 239-252.

Holmes, S. J.

1904. The Problem of Form Regulation. Archiv für Entwickelungsmechanik der Organismen (Roux), Bd. XVII, pp. 265-305.

1907. Regeneration as Functional Adjustment. Jour. Exp. Zoöl., Vol. IV, pp. 419-430.

Wilson, E. B.

1905. The Problem of Development. Science, N. S., Vol. XXI, pp. 281-294.