HYBERNATION OF INSECTS. 461 



tJierniometer was never lower at night than 48", 

 while in the first ^"eek of August it was twice as low as 

 46°, and never higher than 50". 



As a la-t resource, the advocates of the doctrine I 

 am opposing, may urge, that possibly insects may even 

 have their sensations affected by the cold some days 

 before it comes on, in the same way as we know that 

 spiders and some other animals are influenced by 

 changes of weatJier previously to their actual occur- 

 rence. But once more I refer to my meteorological 

 journal ; and I find that the average lowest height of 

 the thermometer, in the week con)prising the latter 

 end of October and beginning of November 181 G, was 

 43^ ; while in the week comprising the same days of 

 the month of the end of August and beginning of Sep- 

 teuiber it was only 44*'* — a difference surely too con- 

 siderable to build a theory upon. 



I have entered into this tedious detail, because it is 

 of importance to the spirit of true philosophizing to 

 show v/hat little agreement there often is between 

 facts and many of the hypotheses, which authors of 

 tlie present day are, from their determination to ex- 

 plain every thing, led to promulgate. But in truth 

 there was no absolute need for imposing this fatigue 

 upon your attention; for the single notorious consi- 

 deration that in this climate, as well as in more south- 

 ern ones, we not unfrcquently have sharp night-frosts 

 in summer, and colder v. eather at that season than in 

 the latter end of autumn and beginning of winter, and 

 yet that insects do hybernate at the latter period, but 

 do not at the former, is an ample refutation of the no- 

 tion that mere cold is the cause of the phenomenon. \i\ 



