432 ESSAYS anp OBSERVATIONS 
vered by the lax internal cellular membrane 
of the womb, will be moft dilated, or put 
on the appearance of finufes ;_ and this effect 
will be moft confpicuous where the greateft 
flow of liquors is, that is, at the place where 
the placenta is attached to the womb; as my 
brother has juftly remarked. 
If we compare the above defcription with 
the common notion of a finus, we fhall find 
they differ widely.—They are generally de- 
fined to be large cavities in the middle of the 
fubftance or flefhy part of the womb, that 
have fmall branches of arteries and veins o- 
pening into them, with canals, whofe dia- 
meter is confiderably lefs than that. of the 
finus, running obliquely thro’ the fubftance 
of the womb to open upon its inner fide.— 
But fince, after a diligent fearch, no finufes 
of this form could be feen in this fubject; 
as neither my brother nor the accurate A/b7- 
nus paint or defcribe any fuch; and, as the 
ingenious and diligent Dr Haller pofitively 
affirms, in one of his lateft works*, that af- 
ter repeated experiments, he could not ob- 
ferve them; it feems probable, that the 
trunks of the veins have been miftaken for 
finufes ; and their branches, for canals opening 
into 
* Prim. Lin. phyf § 804, 
