56 STRUCTURE OF THE LEPIDOPTERA 



species, the other division contains about two thonsancl. Yet, in 

 spite of this fact, luotlis are not generally observed as much as 

 butterflies, for the former are nearly all night-fliers, and the latter 

 always fly by da}' and rest by night. 



Still our question remains unanswered. The reason is this. 

 The captives sent us are seldom caught on the wing. Most of our 

 grown-up friends, even though they admire our own pluck and 

 general carelessness concerning the remarks of the spectators of 

 our entomological antics, would not themselves like to be seen, hat 

 in hand, chasing a butterfly ; and the night-flying moths are, of 

 course, less frequently observed. Bi;t they often, in the course of 

 their daily employments, meet with a large moth fast asleep 

 in some corner of a dwelling house, workshop, or outhouse. Such 

 moths are easily caught while in the midst of their slumbers, 

 and, as they often make no attempt to fly by day, are as easily 

 transferred to a box suitable for transmission by messenger or by 

 post. 



In the above few remarks we have alluded to some features by 

 which the two great groups of the Lepido^Jtera may be dis- 

 tinguished ; but we have already referred (page 5) to a far more 

 important one in our description of the various forms of antennae. 

 All butterflies— at least all British butterflies — have knobbed or 

 clubbed antennae, while the corresponding organs of all our moths 

 terminate in a sharp point. 



This distinction obtains in all British Le2ndo2-)tera, and is so far 

 regarded as the most important basis of classification that natural- 

 ists have derived from it the two Greek terms tliat are synonymous 

 with our two popiilar names — butterflies and moths. The scientific 

 name for the former group is Rhopalocera — a term derived from 

 two Greek words, one signifying a horn, and the other a club, and 

 thus meaning ' club-horned.' The corresponding name for moths 

 is Heterocera, derived from the same source, and meaning ' vari- 

 ously horned.' 



But, although we find embodied in these two long and formid- 

 able names an unerring mark of distinction between British 

 butterflies and moths, we must not neglect other less important 

 facts which, though less distinctive, are not without interest. 



Observe a butterfly at rest. Its wings are turned vertically 

 over its back, and brought so closely together that they often 

 touch. In this position the ' upper ' surfaces of the ' upper ' wings 

 are completely hidden from view, and the ' under ' surfaces are 



