269 
Mr. Yarrell on the change in the plumage, & c . 
advanced period of their lives, and concludes, “ that all hen- 
pheasants as well as common-fowls would assume the plu- 
mage of the cock to a certain degree, if they were kept to a 
certain age/’ 
Some further observations on this subject by Monsieur 
Isidore G. St. Hilaire, will be found in the “ Annales des 
Sciences JVaturelles,” and in the Eleventh Number of Dr. 
Brewster's Edinburgh Journal. 
The remarks I shall have occasion to introduce, will be 
found somewhat at variance with the opinions of the writers 
above referred to, who appear to consider that age is abso- 
lutely necessary to produce this change : I shall be able to 
show, that certain constitutional circumstances producing this 
change, may, and do, occur at any period during the life of the 
fowl, and that they can be produced by artificial means. 
Besides various opportunities during former seasons, I had 
the advantage, in the months of December and January 
last, of examining seven hen-pheasants, in plumage more or 
less resembling the male, in all of which the sexual organs 
were diseased, but with some variation as to extent, and the 
progress of change observable in the plumage bore a corres- 
ponding analogy. The ovarium was contracted in size, of a 
purple colour, and hard to the touch ; the spherical shape of 
the ova destroyed in some ; the oviduct also diseased through- 
out its whole length, and the canal obliterated at the upper 
part immediately preceding the funnel-shaped enlargement at 
the bottom of the ovarium. 
The parts were all preserved, and deposited in the Museum 
of the Zoological Society. 
Desirous of possessing a specimen of the organs from a 
