HABITATIONS OF INSECTS. 467 



sioned to us by these insects is not confined to tlie quan- 

 tity of materials consumed in clothing and feeding 

 themselves. In moving from place to place they seem 

 to be as much incommoded by the long hairs which sur- 

 round them, as we are by walking amongst high grass; 

 and accordingly, marching scythe in hand, with their 

 teeth they cut out a smooth road, from time to time re- 

 posing themselves, and anchoring their little case with 

 small silken cables. 



If, as I hope, you are induced to investigate the man- 

 ners of these insects, you have but to leave an old coat 

 for a few months undisturbed in a dark closet, and you 

 may be pretty certain of meeting with an abundant 

 colony. 



Not merely wool or hair, but another substance 

 analogous to one employed in our dress, is adopted for 

 their clothing by other insects. The larva of a fly which 

 lives on the seeds of willows, makes itself a very beau- 

 tiful case of their cottony down, not only impervious to 

 vv'et and cold, but serving, if accidentally blown into 

 the water, which from the situation of these trees fre- 

 quently happens, as a buoyant little barge which is 

 wafted safely to the shore ^. 



The habitations which we have hitlierto been con- 

 sidering, are formed by larvae that live on land, but 

 others equally remarkable are constructed by aquatic 

 species, the larvae of the various Phryganeoe^ a tribe 

 of four-winged insects which an ordinary observer 

 would call moths, but which are even of a distinct 

 order ^, not having their wings covered by the scales 



'^ f'paum. iii. l.'iO. " See Kirby in Linn. Trans, x't. 88, 



in here it is proijosccl to tall thii order Trkhopiera. 

 2 H 2 



