354 NON-PROGRESSIVE MOVEMENTS. 



gnats and Tipulce lightly skimming, water-bugs gliding with 

 or against the current, whirlwigs describing circles, and all 

 performing their varied evolutions upon liquid plains with far 

 more ease and dexterity than the most accomplished skater 

 when those plains are rendered solid. 



In air, as well as on land and water, various insects exhibit 

 peculiar movements, as well as those shared with other winged 

 creatures. The sportive dancing of gnats and Tipulidan flies, 

 the sailing of winged ants, the beautiful undulating suspension 

 of the graceful Ephemerae, would appear to have no exact cor- 

 respondence amongst feathered fliers ; while of a character no 

 less sui generis are various wing exercises of a non-progressive 

 character performed by insects only. Of this latter description 

 is the flirting by the butterfly of her painted fans, the fanning 

 of bees, and the quivering of his little transparent, black-tipped 

 pinions by the " vibrating fly," l a tiny, scarlet-headed, black- 

 bodied lover of the sunshine and of flowers. 



The purposes of the above and similar actions may still, 

 perhaps, admit of doubt, inasmuch as they have been assigned 

 by careful and intelligent observers to different exciting motives. 

 By some, the butterfly has been supposed to flirt her wings 

 simply with the same cooling intent as that wherewith a lady 

 flirts her fan, while another considers that the " Vanessa," when 

 she fans the air with her pinions, is inviting its entrance into 

 their tubes and nervures, as a preparative for flight; and while, 

 by one, the quiverings of the vibrating fly are supposed to assist 

 its respiration, another, from having noticed these same vibra- 

 tions to be performed only in the sunshine, regards them as 

 expressions merely of delight. 



How can we so often permit our minds to stagnate for want 

 of exercise, when even in an insect movement, and the springs 

 which direct it, there is matter for thought, and doubt, and 

 discovery ! 



Another peculiarity distinguishes the movements of some 

 insects from those of nearly all other animals save man. This 

 1 Scioptera vibrans, Kirby. See Vignette. 



