440 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1925 



BUTTERFLIES IN GENERAL 



No equally large group of insects in which the metamorphosis is 

 complete show such a general uniformity of habit as do the butter- 

 flies. Both sexes of all kinds can fly, though in some the females 

 are more sluggish and less proficient on the wing than males; in 

 a very few the females arc much more frequently seen flying than 

 the males. All are day fliers. Most kinds fly only in bright sunlight, 

 from the middle of the morning until mid afternoon, the females 

 taking wing in numbers considerably later than the males. A 

 number prefer the half light of wooded regions, and a few fly only 

 in the early morning and again at dusk. 



Nearly all caterpillars of butterflies are leaf eaters, living on 

 dicotyledonous plants, and among these apparently preferring cer- 

 tain families. Some, of a special group, and a few others, feed on 

 grasses. A very few, of a queer mothlike type, bore into pith and 

 roots. 



THE LYC^NIDS 



Only in a single group of butterflies does there occur a wide di- 

 versity of habits. This is the group embracing the hairstreaks, blues, 

 and coppers called the Lycwnida^. 



The Lycaenidse are far more abundant in the tropics of both 

 hemispheres than in the temperate zones, but even in the latter, espe- 

 cially in Asia and Europe, they form a large proportion of .the local 

 species. 



As stated by Trimen, the numerous species, though of small size, 

 are, as a rule, remarkable for brilliancy of coloring and exquisite 

 variegation of marking. Richness of hue is, however, usually con- 

 fined to the upper surface of the wings, which in the males often pre- 

 sents one vivid field of metallic orange-red or glistening blue, while in 

 the female it is usually duller, varied with spots, or more suffused 

 with grayish or with blackish, and occasionally Avholly broAvn, 

 presenting a totally different aspect to that of the male. The under- 

 side, on the contrary, differs but very little in the two sexes; it is 

 commonly of some soft shade of gray or brownish, marbled or 

 streaked with transverse darker or paler lines, or with rows of 

 white ringed spots, and is not infrequently ornamented with very 

 brilliant metallic dots, usually on the hind wings. Mr. Scudder adds 

 that the antennse are almost always ringed with white, aod a con- 

 spicuous rim of white scales encircles the eyes. 



THE CATERPILLARS OF THE LYC.^NIDS 



Lyca^nid larvffi are for the most part shaped like wood lice or sow- 

 bugs, and in many cases look more like a coccid or some vegetable 

 excrescence than like a caterpillar. Their legs often are extremely 



