THE BUTTERFLIES AND MOTHS 57 



Measuring- Worms. The measuring- worms (Fig. 36) are the 

 larva; of a group of medium-sized moths, which afford many 

 illustrations of protective re- 

 semblance. When some of 

 these larvae are at rest, stand- 

 ing out stiff from a twig, it is 

 difficult to believe them to be 

 caterpillars. Most of them 

 have three pairs of legs less 

 than other caterpillars, so that 

 a looping gait is the result, 

 whence the name, " measuring- 

 worms." They have the habit, 

 when disturbed, of dropping 

 to the ground on a silken 

 thread, which they spin as they 

 fall. 



Definition of Lepidoptera 

 (Gr. lepis (lepidos), scale; 

 pteron, wing). The butterflies, 

 skippers, and moths, collec- 

 tively, are spoken of as Lepi- 

 dop'tera. The Lepidoptera 

 have four large wings covered 

 with scales, sucking mouth- 

 parts, and undergo a " com- 

 plete" metamorphosis. The 

 larvae, called caterpillars, with 

 few exceptions, feed upon the 

 leaves of plants. They pass a 

 greater length of time in the 

 pupal stage than the other 

 insects we have thus far con- FR; 36 Measuring _ Worms . Natural 

 sidered. size 



