360 



INSECT TRANSFORMATIONS. 



duced, they immediately fly off* The long-legged 

 spiders, popularly called shepherds and harvest-men 

 {Phalangifl{F, Leach), have a similar mode of ele- 

 vating their legs, particularly the second pair, which 

 they move about in all directions. 



/ ) 



a, Phalangium ; b, Hydrometra siagnorum, magnified. 



It can scarcely have escaped the remark of the 

 most indifferent observer, that when butterflies (par- 

 ticularly those of the genus Vanessa) alight during 

 sunshine on a leaf or a pathway, they flirt their 

 wmgs as a lady does her fan, and perhaps, as has 

 been conjectured, for the similar purpose of cooling 

 their bodies. But to us it appears more probably 

 with the design of impelling air into the tubes of their 

 wings to fit them the better for flight ; for we have 

 remarked that they uniformly fan their wings when 

 about to rise, though they had previously remained 

 motionless for an hour together. A pretty family of 

 two-winged flies {Hyrphidce)-\ may frequently be 

 remarked in lanes and on the borders of woods, 

 hovering on the wing for a considerable time without 

 shifting a hair's breadth from their place, though 

 the motion of their wings is all the while so rapid as 

 to be almost imperceptible, similar to some moths 

 {Sphingidce, Pluna gamma^X &c.) while sipping 

 * J. R. f See p. 4. % Seep. 214. 



