164 Of Animalcula in Fluids . 
in two bags, which hang from their fides, or under their 
tail, as in fig. 325. Thefe bags are fometimes feen 
broke, and the fpawn fcattered about the water. There 
is a third fort amongft thefe as beautiful as the foregoing, 
but not near fo large ; its fhape nearly refembles a fhrimp, 
and carries its fpawn as the fhrimp does. Thefe three 
kinds of animalcula have but one eye, and that placed 
in the middle of their forehead ; they are often to be found 
fo tranfparent, that the motion of their bowels is very 
plainly difcovered by the microfcope, together with a 
regular puliation in a little part, which we may fuppofe 
the heart. 
In the fummer-time it is common for the water in 
ditches to appear fometimes of a greenifh, and fometimes 
of a brownifh colour, which upon examination by the 
microfcope is found to confift in infinite numbers of ani¬ 
malcula, blended together on the furface of it, and giving 
it fuch an appearance; their fhape is oval, but the mid¬ 
dle either green or red, feems to be compofed of globules, 
refembling the roes or fpawn of fifhes. 
Of the frefh water polipe, with arms in form of 
horns 5 of their motion and ftrudture. 
r~T*\ H E nature of this infeed is both extraordinary, 
jL and contrary to the general received opinions of 
animal life, and requires the moil: convincing proofs to 
perfuade many people into a belief thereof. In order 
therefore to clear up this peculiar affair, I fhall lay before 
the reader the following obfervations, which were made 
by Mr. Trembly, and alfo affine him, that I have repeated 
the major part of his experiments on this animal with 
the fame fuccefs. 
And 
