Richard Owen: "Hukum Koeksistensi; - adaptasi struktur terhadap fungsi...

"Hukum Koeksistensi; - adaptasi struktur terhadap fungsi; dan sampai batas tertentu, penjelasan afinitas alami dapat secara sah didasarkan pada pemeriksaan spesies yang telah berkembang sepenuhnya; pemeriksaan tahapan perkembangan mereka berturut-turut, di setiap kelompok Hewan."

--- Richard Owen

Versi Bahasa Inggris

The laws of Coexistence;-the adaptation of structure to function; and to a certain extent the elucidation of natural affinities may be legitimately founded upon the examination of fully developed species;-But to obtain an insight into the laws of development,-the signification or bedeutung, of the parts of an animal body demands a patient examination of the successive stages of their development, in every group of Animals.