The "spermist" camp thought it was stored in the spermatozoa, while the "ovists
" argued that it was situated in the ovum, the female egg.
Ovists, including Marcello Malpighi and Jan Swammerdam, argued that a miniature human was housed within each female egg (then recently described by William Harvey); spermists such as Antoni van Leeuwenhoek and Nicolas Hartsoeker argued that each sperm contained little people, or homunculi.
Pinto-Correia avoids a chronological account of the development of preformation, rather structuring the book around each of the challenges to preformation in general, illustrating how ovists and spermists responded differently.
The ovists and the spermists, she insists, were on to something important.
Swammerdam was a committed ovist who deduced from his work on silkworms and other insects that humans existed fully formed, albeit in miniature, inside maternal ova.
His emphasis evokes not Harvey's or the ovists' accounts of the importance of the egg so much as an ancient and enduring myth about pregnant mothers.
23 Gasking describes how the early preformationists were all ovists (48), but beginning with Leeuwenhoek in 1683 animalculists became increasingly popular (56).
Only in one instance did I detect an overly zealous feminist reading: Gelbart makes the point in passing that du Coudray was an ovist
(believing that humans exist preformed within the woman's eggs, not in the man's sperm) and sees this as properly progressive.