132 DEVELOPMENT AND HEREDITY. 



case of the hen-pheasant this has been observed 

 to occur far more frequently during certain years 

 than during others. A duck ten years old has 

 been known to assume both the perfect winter 

 and summer plumage of the drake. Water- 

 ton gives a curious case of a hen who had 

 ceased laying, and had assumed the plumage, voice, 

 spurs, and warlike disposition of the cock. When 

 opposed to an enemy, she would erect the hackles 

 and show fight. . . . The females of two kinds of 

 deer, when old, have been known to acquire horns; 

 and, as Hunter has remarked, we see something 

 of an analogous nature in the human species. On 

 the other hand, with male animals, it is notorious 

 that the secondary sexual characters are more or 

 less completely lost when they are subjected to 

 castration. Thus, if the operation be performed 

 on a young cock, he never, as Yarrell states, crows 

 again ; the comb, wattles, and spurs do not grow 

 to their usual size, and the hackles assume an 

 intermediate character between true hackles and 

 the feathers of the hen. Cases are recorded of 

 confinement, which often affects the reproductive 

 system, causing analogous results. But characters 

 properly confined to the female are likewise acquired 

 by the male ; the capon takes to sitting on eggs, 

 and will bring up chickens ; and what is more 



