1. Caroline Walker Bynum, Metamorphosis and Identity (New York: Zone Books, 2005).
2. Mary Douglas, Purity and Danger (London: Routledge, 2002).
3. Lorraine Daston and Katherine Park, Wonders and the Order of Nature, 1150–1750 (New York: Zone Books, 1998).
4. Daston and Park, Wonders and the Order of Nature (1998), p. 176.
5. See Henry Harris, Cell Fusion: The Dunham Lectures (Oxford: Clarendon Press, 1970).