il: SEMINAL VERMICULi. 47 
the tubes from heat to cold, and vice verfa. We 
mit remark that repetition of this operation: en- 
feebles the vermiculi fo mych, that at laft they 
cannot recover, and perifh for. ever. 
- I withed to learn how long they might remain 
lethargic without deftrudion, fo that removing 
them to a-warm fitaation, they would {till ‘refume 
their original ftrength and jmotion, but I have 
been unable to determine the precife limits : it 
appears to depend in a great meafure on the de- 
gree of cold.to:which they have been fubjeéted. 
If the cold furpaffes freezing, and we delay fome 
hours to remove them: to a warm place, then 
they revive no‘more, or but a few are re-animat- 
ed; and thefe are generally weak and. ill. If 
the cold is lefs intenfe, and the thermometer on- 
ly falls to-41° or 39°, they may remain lethargic 
fourteen. hours, and even longer. Here I do not’ 
intend demonftrating to the reader, that the accis 
dents happening to. vermiculi in capillary tubes. 
completely quadrate with thofe experienced by’ 
animals expofed to cold, and that cold is fatal to 
them, as to many infects: this may be under- 
{tood without explanation. 
If we fhould now unite thefe traits with the 
reft difperfed through this work, with. the death 
of vermiculi by the poifonous exhalations com- 
monly fatal to animalcula, the odour of camphor, 
the oil of turpentine, the fumes of fulphur-and 
tobacco, 
