Haeckel demonstrates the parallelism between ontogenesis and philogenesis-between the successive forms in the evolution of the embryo and the successive forms of the individual in the evolution of a race.
"The Mechanism of Life"
Stéphane Leduc
"In a word," M. de Quatrefages continues, "the learned Genevan professor rightly considers that, 'The ontogenesis of all organic beings without exception, is the normal result of all the various influences which operate upon such beings.
"The Old Riddle and the Newest Answer"
John Gerard
"Phylogenesis is the mechanical cause of ontogenesis"; in other words, "The evolution of the stem or race is-in accordance with the laws of heredity and adaptation-the real cause of all the changes that appear, in a condensed form, in the development of the individual organism from the ovum, in either the embryo or the larva."
"Darwin and Modern Science"
A.C. Seward and Others