Note 41 — Chapter IV · ToC
Reading edition
A similar condition has been noted among butterflies, where, in some cases, differences in the colouring of the wings on two sides has been found to correspond to an internal co-existence of the male and female sex-organs. It seems probable that this interesting phenomenon of abnormal hermaphroditism is of much commoner occurrence than the cases that have been recorded (Evolution of Sex, p. 67).