CHAPTER VI. 



HERMAPHRODITISM. 



§ I. When an organism combines within itself the production 

 of both male and female elements, it is said to be bisexual or 

 hermaphrodite. This is the case with most flowers, and with 

 many lower animals, — such, for instance, as earthw^orms and 

 snails. It is not desirable to extend the term, as is sometimes 

 done, to cases like ciliated infusorians, where sex itself is only 

 incipient. Undoubtedly in those Protozoa recent researches 

 have distinguished what in loose analogy may be called male 

 and female nuclear elements, but this primitive condition is 

 rather a state antecedent to sex, than a union of sexes in one 



anism. 



In most phanerogams, as every one knows, male and female 

 organs occur on different leaves (stamens and carpels) of each 

 flower. The flower as a whole, or the entire plant, may then 

 be called hermaphrodite. But as the male and female organs 

 are restricted to different leaves, each leaf is by itself unisexual, 

 when compared, for instance, with the prothallus of a fern, 

 which bears on the same small expansion both male and female 

 organs. When stamens and carpels unite together, as in 

 orchids, a more intimate hermaphroditism is obviously developed. 

 So with animals. While the general definition of hermaph- 

 roditism, as the union of the two sexes in one organism, is 

 plain enough, the union is exhibited in a great variety of ways 

 and degrees. Of these it is necessary first to take account. 



§ 2. E^nbryonic Hermaphroditism. — Some animals are 

 hermaphrodite in their young stages, but unisexual in adult life. 

 Allusion has already been made to the case of tadpoles, where 

 the bisexuality of youth occasionally lingers into adult life. 

 According to some, most higher animals pass through a stage 

 of embryonic hermaphroditism, but decisive proof of this is 

 wanting. 



