on the Ovaria. 235 
bled to determine, how far it depends on any particular pro- 
perty of the conflitution, or of the ovarium alone. 
As the female of mod; claffes of animals has two ovaria, I 
imagined, that by removing one it might be.poflible to deter- 
mine how far their actions were reciprocally influenced by 
each other, from the changes which by comparifon might be 
observed to take place, either by the breeding period being 
Shortened, or perhaps, in thofe animals whofe nature it is to 
bring forth more than one at a time, by the number produced 
at each birth being diminifhed. 
There are two views in which this fubjeft may be confidered. 
The firft, that the ovarium, when properly employed, may be 
a body determined and unalterable refpefling the number of 
young to be produced. In that cafe we can readily imagine, that, 
when one ovarium is removed, the other may produce its deter- 
mined number in two different ways ; one when the remaining 
ovarium, not influenced by the lofs of the other, will produce 
its allotted number, and in the fame time; the other, when it 
is affebt'ed by the lofs, yet the conflitution demands the fame 
number of young each time of breeding, as if there were ftill 
two ovaria; confequently it furnifhes double the number it 
would have been required to fupply, had both been allowed to 
remain, but muft ceafe from the performance of its function in 
half the time. The fecond view of the fubjeft is by luppofing, 
that there is not originally any fixed number which the ovarium 
muft produce ; but that the number is increafed or diminifhed 
according to circumftances ; that it is rather the conflitution at 
large that determines the number; and that, if one ovarium is 
removed, the other will be called upon by the conflitution to 
perform the operations of both ; by which means the animal 
M m 2 fhould 
