Published online by Cambridge University Press: 31 May 2012
Aparity is that development in reproduction wherein the adult mother retains the eggs instead of laying them. The result is that the young hatch in the mother's body and are forced to feed on her tissues until they have eaten their way out. Such a condition might be construed as parasitism on the adult mother. Since the phenomenon is brought on by the parent and is forced upon the young, it can hartdly be called parasitism, unless the old term obligate parasite is given a new meaning.