46 SEMINAL VERMICULI. IL 
have not been fufficiently numerous to’ folve the 
‘problem. 
We have feen that the motion of feminak ver- 
miculi continues complete days in confined air, 
and it ceafes in a few hours in the open air. I have 
demonttrated that the continuance of life in clofe 
tubes is the confequence of their being fheltered 
from the influence of the air. Fromranalogy, one 
would think that this fhould occur at all feafons. 
But arguments from induétion fhould not be 
ufed by philofophers, fince they are too often 
fupported by deceitful appearances: the prefent 
cafe may afford a newexample. During winter, 
vermiculi in tubes, fealed hermetically, become 
motionlefs in the fame time as in watch-glaffes 
expofed to the open air : nor is cold equal freezing 
required to render them motionleis. In an hour 
and a half, they were motionlefs in capillary 
tubes, as well as in the open air, when the ther- 
mometer ftood at 45°. That vermiculi may 
continue alive in tubes, a certain degree of heat 
is neceflary, which my experiments indicate to be 
52° or 54°. 
When they become motionlefs, it is not always 
a fign of death; fometimes only a fimple lethargy 
takes place. When included im tubes, I have, 
by means of heat, reftored them to their natural 
motion from perfect reft: Motion and reft have 
even been produced fucceflively, by tranfporting, 
~~, the 
