Classification of Insects: Lepidoptera. 177 



are sometimes laid waste by these devourers. They will even fill 

 ditches that have been dug to arrest their progress, aud the only 

 way to control them, is to collect in winter and burn the mosses in 

 which they are concealed. 



696. The Nodum, or owlet moths, chiefly fly by night, and are 

 thick-bodied, swift-flying moths, that do considerable damage to 

 vegetation, and some of them live exposed on the leaves of trees 

 and shrubs, but the greater part feed only by night. 



697. The Geometras, or span worms, live mostly in the larva state 

 only on the leaves of trees, and undergo their transformation in the 

 ground. Their larvae derive their name from their manner of crawl- 

 ing, by drawing up the body into an arch, 

 aud then reaching forward for a new hold. 

 When disturbed, they drop by a silken thread, 

 till the danger is over, and then climb back 

 again to their former place, with a tolerably ^^^ MaiTMoth '^eoeom- 

 rapid motion, by seizing the thread with s^n-wTrmli' °'^^ °^ *''* 

 their jaws and forelegs. 



698. The canker-worm female moths are nearly without wings, 

 and are sluggish in their movements. They in- 

 stinctively make their way from the ground where 

 they have been hatched towards the nearest trees, 

 and slowly creep up the trunks, pairing with their 107.' remade Moth 

 winged mates in their ascent. They are chiefly in- blti^t^uSam^"' 

 jurious to the apple and elm trees, but also attack 



the plum, cherry, and lime trees, 

 and strip them of the pulpy part > 

 of the leaves, leaving the mid- 

 ribs and veins remaining. 



699. The Trniricei, or leaf- 

 rollers, are so called from the 

 cylindrical rolls that they forme's- ^"^ E^kiroi'its" Rl'IgeT' ""^ *'"' 

 around themselves at the close 



of their larva-life. Very few of them make cocoons, and most of 

 them go through their transformations in their leaf-cases. The moths 

 of this tribe are mostly small, and they fold their wings over their 

 bodies when at rest, like a steep roof. Most of them when dis- 



