HOMO LOGY. 87 



herent, but latent, and dependent on causes 

 at present almost unknown. It may here be 

 remarked that no known vertebrate animal 

 is hermaphrodite, except abnormally and im- 

 perfectly. 



The workers in a bee-hive are undeveloped 

 females, but it has long been known that by 

 a special process of rearing, the larva of 

 an ordinary worker can be developed into a 

 perfect queen-bee. A far more extraordinary 

 assertion has been made by an American lady 

 Entomologist, that the sex of butterflies is 

 determined by the greater or less amount of 

 food supplied to the caterpillars.* Her obser- 

 vations, however, have not yet been confirmed,, 

 and as some caterpillars exhibit sexual differ- 

 ences in that state, it would require very careful 

 and prolonged experiments before such a fact, 

 could be considered fairly established. 



Still less are the secondary sexual characters, 

 exclusive attributes of either sex. Darwin 

 observes f " In many, probably] in all cases, the 

 secondary characters of each sex lie dormant or 

 latent in the opposite sex, ready to be evolved 



* Mrs. Treat, American Naturalist, vol. vii. 



t " Variation of Animals and Plants under Domestication," vol.ii.p.52. 



