174 Mr. Home's Account of the 
of men. The circumstance of some women, after the time of 
breeding is over, (at which period the influence of the ovaria may 
be considered as lost to the constitution, ) approaching nearer to 
the male in appearance, and acquiring a beard ; also the female 
pheasant and duck,* in several instances, at the same period of 
their life, acquiring the feathers which distinguish the male, so 
as to be mistaken for males, is in favour of such an opinion. 
The histories of monsters which have superfluous parts, as 
that of the child with the double head,-f and all others of the 
same kind, lead to the opinion of two or more foetuses having 
been contained in one ovum, similar to two yolks in one egg ; 
and that, from some circumstance having taken place in utero, 
certain parts of one of the foetuses were prevented from coming 
to perfection, and were absorbed ; while those that remained 
became connected to the other foetus. 
* The following account of a duck of this kind was sent me by Mr. Rum ball, 
surgeon, at Abingdon, in Berkshire. 
The duck was bred by Mr. Cator, of Norwood, in Surrey, in the year 1781. It 
continued to lay, and to hatch its young, till the year 1789 ; when the curled feathers, 
peculiar to the drake, made their appearance in its tail. From this period, she not o ily 
left off laying, but frequently attempted to tread the other ducks, both in the water, 
and upon the ground ; and they courted her in return. This was particularly observed 
on the 19th of August, 1791, when she trod a duck in the water, and fell off on her 
side, as drakes usually do ; and they both began washing themselves immediately after, 
as is customary on these occasions. She never afterwards suffered a drake to come 
near her. 
Although the plumage changed, the voice continued the same, which is very diffe- 
rent from that of the drake. This circumstance first attracted Mr Rumball’s notice, 
and made him doubt of its being really a drake. On the 14th of October, 1793, at 
the request of Mr. Rum ball, this duck was sent to Mr. Hunter, and died on the 
18th, two days after Mr. Hunter’s death. On examination, the organs of genera- 
tion were those of a perfect duck. The skin is stuffed, and preserved in Mr. Hunter’s 
collection . 
f Phil. Trans. Vol. LXXX. p. 296, and this Vol. p. 28. 
