IMPERFECT SOCIETIES OF INSECTS. 7 



" Some to the sun their insect wings unfold, 

 Waft on the breeze, or sink in clouds of gold; 

 Transparent forms, too fine for mortal sight, 

 Their fluid bodies half dissolv'd in light; 

 Loose to the wind their airy garments flew, 

 Thin glittering textures of the filmy dew, 

 Dipt in the richest tincture of the skies, 

 Where light disports in ever mingling dyes, 

 While every beam new transient colours flings, 

 Colours that change whene'er they wave their wings." 



I wish you may have the good fortune next year to be 

 a spectator of this all but celestial dance. In the mean 

 time, in May and June, their season of love, you may 

 often receive much gratification from observing the mo- 

 tions of a countless host of little black flies of the genus 

 Hilm-a^ {H. maura,) which at this period of the year 

 assemble to wheel in aery circles over stagnant waters, 

 with a rush resembling that of a hasty shower driven by 

 the wind. 



The next description of insect associations is of those 

 that congregate for the purpose of travelling or emi- 

 grating together. De Geer has given an account of the 

 larvae of certain gnats (Tipularice) which assemble in 

 considerable numbers for this purpose, so as to form a 

 band of a finger's breadth, and of from one to two yards 

 in length. And, what is remarkable, while upon their 

 march, which is very slow, they adhere to each other by 

 a kind of glutinous secretion ; but when disturbed they 

 separate without difficulty ^. Kuhn mentions another of 

 the same tribe (from the antennae in his figure, which is 

 very indifferent, it should seem a species of agaric-gnat 

 {Mycetophila), the larvae of which live in society and 



" De Geer, vi. 338. 



