THROUGH THE YEAR 47 



STUDIES OF FLIGHT 



There is a feature of the hovering of that odd 

 little insect, the lesser bombilius, which is worth 

 watching. Whilst bombilius is whirring over the 

 sandy road or the garden path, it is not stationary 

 for more than a few seconds, together. Bombilius 

 is constantly swinging or swept away six inches or 

 so, though after each swing it is swiftly back again 

 over the same foot or so of ground. I have noticed 

 the same kind of movement in other whirring insects. 

 There is the ghost-moth, which I watched closely 

 in the thick meadow grass at Oakley in Hampshire, 

 in June 1905, 1906, 1907. The ghost -moth swings 

 somewhat in pendulum fashion whilst it whirrs. 

 It is not steady or fixed in the air for long. Second, 

 there are the syrphi, strange impetuous insects that 

 dart or swing off with much decision during their 

 hover. Third, volucella darts or swings, whilst 

 hovering, like syrphus. It is most singular, this 

 action as if the insect shot itself away a few 

 inches or a foot by some spring or mechanism 

 distinct from the wings. 



Watching the lazier movements of bombilius (those 

 of volucella and syrphus are sharper and more 

 decisive), I wondered whether the thing were passive 

 rather than active in this insect whether it were 

 swept a little from its fixed point for whirring by 

 some little gusts or whiffs of wind blowing at the 

 time. But I doubt now whether the wind has any- 

 thing to do with this shifting of bombilius and other 

 insect hoverers. 



