LETTERS FROM ALABAMA. 
77 
fragrance. They are also called milkweed, from 
the white glutinous fluid, highly acrid, which 
exudes from the stalk and leaves when broken, 
and also butterfly weed^ because they form such 
an attraction to those brilliant insects. From this 
little hill an extensive, but not very pleasing pro- 
spect is visible, little being seen but the summit of 
an almost endless forest, varied here and there by 
the white smoke curling up from some dwelling 
hidden in its recess. Hither I frequently come 
to spend an hour entomologizing, and never fail to 
be well rewarded. 
One of the most numerous of the many species 
that gaily flutter their brilliant wings in the burn- 
ing beams of almost vertical noon, and contribute 
so much to the life and beauty of nature by their 
presence, is the Blue Swallowtail [PwpiUo Philenor, 
Boisd.). The upper surface of the fore wings is dull 
black, generally spotless, but the hind wings have 
a remarkable gloss, bright blue in one light and 
greyish green in another, with a row of white spots. 
Beneath, a row of large crescent -shaped spots of 
bright orange marks the hind wings, and one of 
round white spots the fore pair. The tailed appen- 
dages of the wings , are short, sometimes being 
scarcely more developed than those of a Vanessa. 
I have taken these fluttering about the heads of 
the orange milkweed, their abdomens filled almost 
to bm^sting with the yellow nectar of these flowers, 
and so distended that the division of the segments 
are obliterated, and are discernible only by being 
bare of the scaly plumage. When in this state 
they seem unwilling to fly, but either remain at 
rest, or run to and fro over the blossoms, keeping 
their hind wings in a vibratory, quivering motion. 
