NORTH AMERICAN 



BUTTERFLIES. 



RHOPALOCERA. BUTTERFLIES. 



Antennae, thread-like, terminating in a club-like ex- 

 pansion. Wings, at least the anterior, elevated when in 

 repose. Flight, diurnal. 



Although the four flimihes of scalj-wiiiged insects 

 grouped together under the above heading, do not consti- 

 tute an absolutely natural division, all of our butterflies 

 may be distinguished by the fact that they possess a com- 

 bination of these characters. The antennae of moths are 

 often feather-like, (Fig. 1, b.) that is there are bristle-like 

 appendages to the joints of the antennae. Sometimes they 

 are thread-like, ( ib. c ) but ^. , 



are not enlarged at the ex- 

 tremity. Some species of 

 moths, however, possess an- 

 tennae that are enlarged to- 

 wards the extremity, nota- 

 bly the sphinges, ( ib. d ) but 

 these not only differ widely 

 in structure from butterflies, 

 but the wings are never el- 

 evated when the insect is in 

 repose ( Fig. 2 ). Besides, the sphinges and many other 



B 



D 



E 



A, clubbed antennae of a butterfly ; B, feath- 

 ered antennae ofamoth; C, thread-like antennae 

 ofamoth; D, enlarged antennae of a sphinx; E, 

 hind wing of a sphinx moth, showing hook, o, 

 enlarged at L. 



