THE GOSSAMER-WINGED BUTTERFLIES 



have been studied more carefully in this than in other species. 

 There is a slit on the middle line of the dorsal part of the 

 seventh abdominal segment. From this opening the cater- 

 pillar can protrude a membranous vesicle, from the summit 

 of which exudes a small drop of clear, sweet fluid, a kind of 

 honey-dew. Ants feed upon this ; and there doubtless exists 

 between the Lycasnid larva; possessing this organ and various 

 species of ants relations similar to those existing between 

 aphids and ants ; as Mr. Edwards observed an ant successfully 

 defend a larva of the spring azure from an attack of an ichneu- 

 mon-fly. Upon the eighth abdominal segment there is a pair 

 of openings from each of which can be protruded a membra- 

 nous tube, furnished at the tip with numerous, long, slender 

 tentacles. These in turn are armed with fine filamentous 

 spurs disposed in whorls. The function of these organs has 

 not been determined ; they may be scent-organs for the 

 attraction of ants. 



Caterpillar. — Length, two-fifths of an inch; slug-shaped, 

 dark brown head. Body white with a dusky line down the 

 back and a greenish tinge along the sides. 



Food-plants. — Dogwood, Actinomeris, black snakeroot, su- 

 mac, Spiraea, and others. 



In the early spring when we are weary of 

 winter this butterfly appears in our path like a 

 fleck of the welcome blue sky above. It flits 

 about on uncertain wing or loafs about damp 

 places or hovers about the forest mantle. It is 

 one of the butterflies that we have repeatedly 

 seen winging lazily in and out the topmost 



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