266 THE ENTOMOLOGIST. 



agitated for twenty yards around by a sudden jerk of one's 

 weight. Persons residing in the locality contend, with some 

 show of reason, that miles of these bogs actually float; and 

 to bear this statement out it is asserted, that on certain spots 

 immense quantities of soil have been added to the surface, 

 but in all cases it eventually sinks to the original level ; 

 therefore, whatever becomes of Wicken Fen, the fens of 

 Norfolk, where Machaon is to be found, are not likely to be 

 materially interfered with, — the quality of the soil is of the 

 poorest possible description, — if even the possibility of drain- 

 ing on a large scale existed. I attach but little significance 

 to the fact of a single specimen of this insect being found 

 upon a garden-wall in any particular locality. Machaon is a 

 strong flyer; and it being the custom now-a-days to say 

 when a rarity is captured tliat it must he blown over 

 (especially by entomologists who do not happen to capture 

 them), can it not with propriety be conjectured that these 

 isolated specimens of Machaon have escaped from breeding- 

 cages, or travelled from a distance comparatively easy as 

 compared with a journey over sea. There are many reasons 

 which induce me to believe that but few localities are favour- 

 able to the natural production of this insect, notwithstanding 

 the fact of the plant on which it feeds being abundant in all 

 marshy districts. Amongst the great numbers of the larva) I 

 have from time to time taken, not a single ichneumon has 

 been amongst them, yet if the larva is left exposed, away 

 from its native habitat, the result is the reverse. In the year 

 1868 the larvae were as plentiful as ever. In 1869 I again 

 paid a visit to the Norfolk fens; but being a kw weeks 

 earlier in the season than usual, 1 succeeded in finding forty - 

 nine eggs within a radius of about twelve yards : curiously 

 enough, although the young larvae emerged from the eggs 

 nearly simultaneously, the greater portion fed rapidly, turning 

 to pupae, and in a fortnight produced the ])erfect insect; a 

 few others arrived at maturity after remaining in pupae till the 

 following May, while four remained in the chrysalis state a 

 year after that, thus showing that, although the eggs were to 

 all appearance from the same brood, the greater portion 

 escaped from the chrysalis in two weeks, whilst others 

 remained dormant for two years, although the whole were 

 confined in the same breeding-house. The beautiful larva of 



