If we were capable of following the progress of increase of the number of the parts of the most perfect animal, as they first formed in succession, from the very first to its state of full perfection, we should probably be able to compare it with some one of the incomplete animals themselves, of every order of animals in the Creation, being at no stage different from some of the inferior orders; or, in other words, if we were to take a series of animals, from the more imperfect to the perfect, we should probably find an imperfect animal, corresponding with some stage of the most perfect, (in Owen, 1841, p. 14)

But two observations vitiate Hunter's claim to paternity for the idea of recapitulation as a sequential repetition of "lower" adults: first, although secondary sources (Meyer, 1935, p. 381)2 usually give the date of this passage as about 1755, when Hunter began his work on development of the goose, Owen himself dates the manuscript between 1775 and Hunter's death in 1793—well within the period when basic tenets of Naturphilosophie were being disseminated, though before the traditional date, 1793, for Kielmeyer's inception of the spe- cific argument. Second, Hunter's passage is short, disconnected, and speculative, and is not based on observation. Hunter merely conjec- tured about the course of development before any embryonic structure could be resolved by the best microscopes then available. The next sentence in Hunter's manuscript, although never cited in the litera- ture on recapitulation, makes this clear: "But all our observations can only begin at a visible stage of formation, prior to which we are left to conjecture" (Owen, 1841, p. 14).

Ontogeny and Phylogeny in the Conflict of
"Evolution" and Epigenesis:
The Idyll of Charles Bonnet

Needham spoke of epigenesis and preformationism as "an antithesis which Aristotle was the first to perceive, and the subsequent history of which is almost synonymous with the history of embryology" (1959, p. 40).

What greater mystery can there be than the growth of something so complex as a human baby from humble beginnings in an essentially formless egg or, as Aristotle would have it, the menstrual blood? The two extreme solutions have their strengths and problems. One can believe what one sees and argue that parts are formed sequentially by external forces acting upon matter only potentially capable of normal development (epigenesis). But what natural force could then regulate ontogeny? Indeed, the eighteenth-century epigeneticists often took refuge in vitalism or outright mysticism. Or one can label what one observes as mere appearance and contend that the complexity of the