f ^39 ) 
ferved in Mar&s, and Glandidiferous Animals. He might' 
have made abetter guefs ac the figure, fite, &c\ of 2i 
Humane AlUntois from that of a Whelp, which does not- 
every where encompafs the Fcetus^ as he obferves. 
Bidloe in mofl: ot liis Figures ot t\\^ Secimdi?7es, 
letters fomc Fejiigia of the Dritrary Membrane, but in 
any of thefe figures^ you only fee broken pieces of 
one, fo confufedly placed, that no Idea of its Bignefs, 
Shape, or Situation can be formed from them. 1 muft' 
confefs that oftentimes the Membranes of the Secundines 
are fo torn, that no Art can exhibit an entire 
However, am.ong the many Seawd'wes that have come 
under the hands of Anatomifts, feveral no doubt muft 
have beea entire enouglifor a fuller difcovery than th^ey 
have made, had it not been by their ways of proceeding" - 
( viz, by knife, fi^^ngers,or blowing under the Chorion) im- 
poffible to dilcover any thing plain, pr fatisfaftory, even, 
in the the tairefl: fubj:::fl:s. 
I come now to anfwer the objeftions of thofe who 
ft ill deny an Urinary Membrane to a Humane Fo^tusi 
The difficuhy of rinding this Memhrant is by no means 
an argument againft theexiftence of itrBut a Woman that 
dies big with Child is fo fair a fubjeft for the difcovery of 
threeMenioranes,l\\'Sii 1 wonder{'/JP^^rej/ having fuch an op-^^^ 
portunity could find but two, if he was fo careful as^^^ 
he fays he was.The accurate Dr Tyfon obferved three Mem- 
branes fome years ago,in a likeTubjeft, After the Chorion 
was divided.and laid afide,he faw two Bladders.conmniug 
Liquors of different colours, which he prefiing one to- 
wards the other, did not mix, but remained diftinft. 
This obfervation fully fatisfied that great Anatomift,to as 
the exiftence of an Allantois 5 and its figure, texaire, fite, 
d^c. might alto have been difcovered by him, had not 
the lefs curious Speftators been impatient to pa fs. on to- 
other parts of the Diffeaion. 
Some- 
