2^4 Mr. Hunter’s Experiment 
appellation of male and female, and equally neceftary to the 
propagation of the animal ; the tefticles, with their appen- 
dages, conftituting the male; the ovaria, and their appendages, 
the female fex. 
As the ovaria are the organs which, on the part of the 
female, furnifh what is neceftary towards the production of 
the third, or young animal ; and as females appear to have a- 
limited portion of the middle ftage of life allotted for that 
purpofe; it becomes a queftion, whether thofe organs are worn 
out by repeated adls of propagation ; or whether there is not a 
natural and conftitutional period to that power on their part, 
even if fuch power has never been exerted ? If we confider 
this fubjedt in every view, taking the human fpecies as an 
example, we fhall difeover that circumftances, either local or 
conftitutional, may be capable of extinguifhing in the female 
the faculty of propagation. Thus we may obferve when a 
woman begins to breed at an early period, as at fifteen, and 
has her children fa ft, that fhe feldom breeds longer than the 
age of thirty or thirty-five ; therefore we may fuppofe, either 
that the parts are then worn out, or that the breeding confti- 
tution is over. If a woman begins later, as at twenty or 
twenty-five, fhe may continue to breed to the age of forty or 
more ; and there are, now and then, inftances of women, who, 
not having conceived before, have had children as late in life as 
at fifty years or upwards. After that, few women breed, even 
if they fhould not have bred before ; therefore, there muff be a 
natural period to the power of conception. A fimilar flop to 
propagation may likewife take place in many other clafles of 
animals, probably in the female of every clafs, the period 
varying according to circumftances ; but ftill we are not ena- 
7 bled 
