An irrefutable proof that such single-celled primaeval animals really existed as the direct ancestors of Man, is furnished according to the fundamental law of biogeny by the fact that the human egg is nothing more than a simple cell.
Ernst Haeckel, Sir Edwin Ray Lankester, L. Dora Schmitz (1906). “The History of Creation: Or The Development of the Earth and Its Inhabitants by the Action of Natural Causes. A Popular Exposition of the Doctrine of Evolution in General, and of that of Darwin, Goethe, and Lamarck in Particular. From the 8th German Ed. of Ernst Haeckel ... The Translation Rev. by E. Ray Lankester”