4586 Insects. 



feeling of pain in insects, that when impaled they often struggle 

 violently and writhe themselves about, but I believe it is well known 

 (I have experienced it myself over and over again) that moths and 

 beetles, and other insects, may be impaled when at rest and show no 

 knowledge of it, but take hold of the pin and remove the insect from 

 its position, and it will struggle and writhe immediately ; replace it, so 

 that its feet may again have a firm hold, and it is perfectly quiet; and 

 this is sufficient to show that no argument can be drawn from the fact 

 of struggling and writhing, since these are evidently excited by some 

 other cause, and are not therefore necessarily connected with pain. 

 Again, it is well known to collectors that when insects still alive are 

 pinned in the collecting-box, a cool situation will keep them perfectly 

 quiet for any length of time, but bring them into a warm atmosphere, 

 and all their wings are set fluttering immediately, though some, and I 

 may particularly mention Eulepia cribrum as an instance, will not 

 move, either in a cool or warm position, until their time of flight 

 arrives. No one will, I think, argue from this that the temperature 

 affects their feelings ; the simple explanation of the circumstance ap- 

 pears to me to be that their muscular activity alone is instantaneously 

 awakened or lulled by changes of time and temperature, in this their 

 impaled state, as we know it is in their state of liberty. If a warm 

 atmosphere were essential to the activity of insects, it would afford 

 ground for supposing that other properties and senses, as feeling, &c, 

 might also be awakened by it ; but it is not essential, for some species 

 C. Brumaria, for instance, may be seen in a state of the greatest 

 activity during the coldest nights of winter. Nor am I aware that 

 any degree of cold or heat raises or lowers the temperature of the 

 insects themselves, though this is a fact which requires experiment to 

 put it beyond doubt. Bees, indeed, it is well known, generate a con- 

 siderable degree of warmth, even in the depth of winter, but this also 

 is a fact now, I believe, unaccounted for. 



I have thus set down in a cursory way, and without attempt at any 

 methodical arrangement, the considerations which appear to me to 

 lead to the irresistible conclusion that insects, and many others of the 

 lower orders of the Creation, but insects especially, are by no means 

 susceptible of the acute corporeal sensations that man and other warm- 

 blooded animals undergo. In recapitulation, therefore, of these con- 

 siderations in a more regular order, it appears that — 



First, from a comparison of the effects, both physical and as 

 shown by outward demonstrations of inflictions and injuries on warm- 



