( 5°7 ) ■ 
f ome fufpicions I had of the like watery Bags,or Bydattdes I 
had met with in other Animals, for from what I could 
then obferve, I was apt to believe them to be a particular 
fort oflnfe&bred in animal Bodies, but fo different from 
any obferved out of them, that unlefs upon fuller and 
farther confiderations, Idurft not truft my own thoughts 
about them. 
My prefent Reafons of fufpe&ing them to be Infe&s, 
or at leaft theEmbrioes or Eggs of them, are thefe, 
Firft, Becaufe I obferved them included in an outward 
Membrane like a Matrix, fo loofely, that by opening it 
with my Fingers or a Knife, the inward Bladder contain- 
ing the Lympha or Serum^ feemed no where to have any 
connexion or hold to it, but would very readily drop out, 
ftill holding its Liquor without fpilling any of it. Upon 
repeated Experiments of it in this, and other Animals, 
it gave me opportunity to think how it was poffible this 
Humour could come into the inward Bladder without 
any cohaefion to the outward which involved it. 
Secondly, Obferving them farther by my naked Eye, I 
perceived that to this inward Bladder there was a Neck 
or white Body, more opake than the reft of the Bladder, 
and^ptotuberant from it : but fo as I could obferve an 
Orifice at the extream of ir, which then to me feemed 
to be occafioned by the retraftion of fome part of it 
inwards. By this I fanfied it might as by a Mouth, 
fuck^ the Serum from the outward Membrane, and fo 
fupply its Bladder or Stomach. 
Thkdly, But in this Thought I was farther encouraged 
by thealjiftance of my'very good friend Mr. Packard Waller, 
Whofe ptefence I defired at the Diffeftion, and by im- 
parting to him my thoughts, that thefe Uydatides might 
be a peculiar fort of Infers bred in Animal Bodie? ; we 
were refolved to fatisfie our felves of the Notion, and 
having obferved what I have before mentioned, we found 
that this Neck (upon approaching it to the CandleJ did 
