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lionidse found in England is about seventy-two: 

 of this number not more than fifty are to be 

 met within twenty-five miles of London ; of 

 these again, several are confined to the vicinity 

 of a chalk cliff, or are peculiar to a meadow or a 

 certain wood ; and, even in these situations, 

 their appearance in the perfect state is limited 

 but to a few days, and at a certain season of the 

 year. Of the remaining number, not found 

 within this distance from London, some are 

 confined to fens near a hundred miles from the 

 metropolis, and others to the mountains of 

 Scotland ; but equally limited in the times of 

 appearance and shortness of their lives. There 

 is also another circumstance in the history of 

 these insects that must not be passed over in 

 silence ; that there are several species of insects 

 which, from some hitherto unknown cause, ap- 

 pear in the season, but only in certain years, 

 when they will be found in abundance, and 

 probably extended over a vast tract of the 

 country, but again disappear for sometime, and 

 not a single specimen is to be found for a period 

 of many years, when they will again be seen as 

 plentiful as before. This is a circumstance 

 that is not confined to England, where it might 

 be attributed to our "ever varying clime:" it 



