Dissection of an Hermaphrodite Dog. 175 
Where monsters are imperfect, there is no difficulty in 
accounting for any organ, or other structure, not having been 
completely formed ; but, that the ovaria should be wanting, and 
their place supplied by testicles, is not to be explained upon the 
same principle. 
The testicles being substituted for the ovaria, and the ovaria 
themselves entirely wanting, is probably the most curious cir- 
cumstance that is met with, in the structure of these hermaphro- 
dites ; and, as many important discoveries in the animal oeco- 
nomy have been suggested from the examination of monstrous 
productions, it naturally leads to the inquiry, whether there is 
any thing in the original formation of the parts, which can ac- 
count for so strange an occurrence. 
The only mode in which it can be explained, as far as I am 
able to judge, appears to be the following. By supposing the 
ovum, previous to impregnation, to have no distinction of sex, 
but to be so formed as to be equally fitted to become a male or 
female foetus ; and that it is the process of impregnation which 
marks the distinction, and conduces to produce either testicles 
or ovaria, out of the same materials. 
The following circumstances are in favour of this opinion. 
The testicles and ovaria are formed originally in the same 
situation, although the testicles, even before the foetus has ad- 
vanced to the eighth month, are to change their situation, to a 
part at a considerable distance. 
The clitoris, in foetuses under four months, is so large as to 
be often mistaken for a penis. Preparations to show the size of 
the clitoris at this age are preserved in Mr. Hunter's collection; 
and M. Ferrien mentions it, with a view to explain an erro- 
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