466 M EM OIR S of the 
upon laying it afuncler he law not only fome hair, but alfb a 
piece of the foot, part of the eye and of the wing, befides fe- 
vcral pieces of the fkin of an animal, which he judged to be 
a fmall infci^t, whofe wings are covered with a (heath, very 
like thofc called beetles j thefe excrements lay in a clear moi- 
fture round them, wherein fwam or creeped fome eels, or 
about 50 Imall worms ^ the fore and hinder-parts of whofe bo- 
dies were very clear -^ thefe eels in the frog's excrements arc 
very like thofe found in vinegar, if not altogether the fame ; 
only with this difference, that^he eels in vinegar, as they are 
taken cut of the mother's Uterus, are fomewhat thinner and 
harder 5 in the firft excrement M. Leeivenhoek difcovered only- 
two of thefe eels^ when he looked next day, and faw that the 
moifture wherein the eels fwam, was partly evaporated, and 
that the eels moved but very little, he put fome rain water 
about the excrements where all the worms and eels were, and 
that water he put into ^ fmall glafs-tube, wherein were fix 
eels, thinking to keep them alive, and obferve whether they 
would breed any young ones 5 yet he found the contrary, for 
they moved Icls, and within a few hours after, fome were 
quite motionlefs 5 and next day he faw, after ftricl examina- 
tion, only a part of an eel 5 from which he concluded that the 
eels were diflblved in the water : The frog had, by its motions 
in the glafs-tube, fo feparated the firft excrement, that M. Lee- 
"wenhoek faw almoft the whole wing of a flying infcfl, about 
the bignefs of a gnat, and this was almoft quite entire, fo that 
he could fee perfe611y the great number ot fmall hairs, which 
grew all over the outfide, and alfo upon the edge of the wing 5 
underneath this wing he faw three of the faid eels, and ano- 
ther in another place, that had ftill a ftrong motion ; on the 
fourth day after the excrements were made, he faw fome eels 
which were alive, both above and under the wing • and be- 
caufe the moifture wherein they lay was but very fmall, £0 
their motion was but little, and afterwards he could perceive 
no motion at all : From thefe obfcrvations M. Leeis)enboek con- 
cludes that water was not proper for thele eels, and that they 
either came out of the ground, or that the animals the frog fed 
upon, were loaded with them; on the fifth day the frog had 
fouled again, and it lay oblong againft the glafs, without any 
moifture at all ; he took it out of the glafs and fpreading it 
abroad, becaufe it appeared blacker to the eye than the 
former, and therein he alio faw parrs of flying infefisj 
and in this there alfo lay feveral of the abovementioned eels, 
but 
