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CHAPTER VII. 



Deposita sarcina, levior volabo ad ccelum. S. Jerome. 



HAVING now completed the short task which I had 

 undertaken to perform, I will, in conclusion, offer a few 

 brief comments on the results at which we have arrived, 

 and endeavour to realize to what extent the considera- 

 tion of them is likely to be found useful, during our 

 inquiries into the general subject of entomological 

 geography. 



Commencing with the thesis, that specific variation, 

 whether as a matter of experience or as probable from 

 analogy, does ipso facto exist; I have endeavoured to 

 maintain that position, by evidence of divers kinds ; and 

 I have sought to strengthen the inferences deduced, by 

 an appeal to some of those external agents and circum- 

 stances which may be reasonably presumed (if not 

 indeed actually demonstrated) to have had a consider- 

 able share in bringing it about. I have also suggested 

 what the principal organs and characters are, in the 

 Insecta, which would appear to be more peculiarly 

 sensitive to the action of local influences; and I have 

 then diverged to the question of topographical distribu- 

 tion, in connection with the geological changes on 

 the earth's surface ; and, lastly, to some practical hints 



