174 ELEMENTARY ENTOMOLOGY 



recognizable groups. The caterpillars of the different families may 

 be recognized, to a certain extent, by their habits and general 

 appearance. The butterflies and motlis form two main divisions 

 of the order, which are readily distinguished. 



BUTTERFLIES 



The butterflies are day fliers, and when at rest the wings are held 

 in a vertical position over the back. The antennae are threadlike 

 and are distinctly enlarged at the tip. 



The butterflies are much less numerous than the moths, both 

 in families and in species, and include relatively few species 



of any considerable 

 economic importance. 

 Two main groups of 

 butterflies are recog- 

 nized, - -the skippers 

 (Hesperind) and the 

 true butterflies (Pa- 

 pilionind]. 



SKIPPERS 

 The skippers are 



FIG. 260. Hop-merchant butterfly, showing form of ra ii~H f rnrn t u p j r 



knobbed antenna of butterflies 



peculiar habit of dart- 



(Photograph by Fiske) 



ing suddenly from 



place to place. The wings are held vertically over the back when 

 at rest, though often the hind-wings are held horizontally. The 

 antennae are enlarged at the tip, which usually forms a more or 

 less recurved hook. They have stout bodies, which resemble 

 moths more than butterflies. Some are blackish or dark, somber 

 brown, often flecked with grayish or white, while others are tawny 

 yellow with a blackish discal patch. The latter usually have the 

 fore-wings much more pointed, and have thick bodies. The larvae 

 of our common forms have a characteristic appearance (Fig. 261), 

 with large heads and strongly constricted necks. They feed on 

 foliage, usually concealing themselves within a folded leaf, which 

 is tied together with silk and within which they spin a loose cocoon 



