Butterflies are mainly diurnal in their habits, preferring the sunshine. Moths 

 on the other hand are nocturnal, and fly in the dusk, or after dark. Butterflies are 

 therefore often called diurnal lepidoptera, and moths are spoken of as nocturnal 

 lepidoptera. There are, however, a few butterflies which fly at dusk, and there are 

 many moths which are diurnal in their habits. Such moths are generally gay in 

 color, and for the most part inhabit tropical countries, although we have a few such 

 species in the United States. Ordinarily the best way to distinguish between 

 butterflies and moths is by examining their antennae, or "feelers," as they are 

 sometimes incorrectly called. In the case of butterflies the antennae are thread-like, 

 terminating in a small knob-like, or club-like enlargement. It is this fact which has 

 led naturalists to call thern Rhopalocera. The word is derived from the Greek 

 nouns puira\ov (rhopalon) meaning a club, and Ktpas (keras) a horn. Butterflies are 

 lepidoptera having at the end of their antennae clubs, which are sometimes short, long, 

 or hooked (see Plate A, Figs, g, h, i.) The forms assumed by the antennae of moths 

 are very various. The moths are therefore known as Heterocera, the word being 

 compounded from the Greek adjective erepos (all sorts) and the noun Kepas (keras) 

 a horn. Moths are lepidoptera having all sorts of antennae, except such as are club- 

 shaped at their ends. However there is no rule without its exceptions, and there 

 are a few rare moths in tropical lands which have club-shaped antennae like butter- 

 flies, but none of these occur in the region with which this book deals. 



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