[ 643 ] 
or even the fame at different times, will at fome 
give the fpermatic Animals immediately, but at 
others not fo foon, and perhaps not under fome 
Hours : which is the Reafon why they have often 
been faid by Naturalifts, and even by Lewenhoeck 
himfelf, not to have been found upon Infpedion. 
By this it will appear, that we had tried many Sorts, 
before we had the good Fortune to meet with one, 
in that exad Degree of Exaltation neceflary to ex- 
hibit the whole Procefs of this Vegetatioil ; and fo 
may others who fhall be defirous of trying thefc 
Experiments after us: Yet, when they fhall at laft 
have obtain’d a proper Subjed, one accurate View 
will be fufficient, and found to give the Key to the 
whole Secret. 
§ 25. When we had feized this favourable Op- 
portunity, we faw a fmall Portion of male Semen 
plac'd on the Microfcrofcope, fir ft, as it were to 
develope and liquefy, then fhoot out into long Fi- 
laments, ramify on every Side, thefe open and di- 
vide into moving Globules, and trailing after them 
fomething like long Tails ; thefe Tails were fo far 
from being Members given them to fwim and 
fteer by, that they evidently caus’d in them an infta- 
ble ofcillatory Motion; and were in Effed nothing 
more than long Filaments of the vifeid feminal 
Subftance which they necefiarily trail’d after them; 
they were of various Lengths in various Animals, 
and they infenfibly, by the continual progreflive 
Motion of thofe Animals, grew fhorrer and fhorter, 
till lome of them appear’d without any at all, fwim- 
ming equably in the Fluid. It was then plain how 
thefe Animals were to be clafs’d ; their Origin was 
clearly to be deriv’d from Principles contain’d in. 
this 
