THE MILKWEED BUTTERFLY 
39 
species been successfully reared through all its stages in Europe, 
and that was in 1911, when I succeeded in doing so by 
obtaining eggs from a living female sent me on August 8th, 
1911, from Hanover, 
N.H., by Mr. Gerould. 
Egg. The egg is small 
in comparison with the 
large size of the butter¬ 
fly, being only 1*3 mm. 
high, of a conical shape, 
closely resembling an 
acorn. There are from 
twenty to twenty-three 
longitudinal keels, about 
fourteen of these run 
the entire length from 
summit to base, and 
there are about thirty- 
four transverse ribs 
which cover the whole 
surface, excepting the 
micropyle, which is re¬ 
ticulated with a network 
pattern. When first laid 
the colour is a very pale 
primrose-yellow, and re¬ 
mains unchanged until 
the third day, when it 
then changes to pearl- 
white,'mottled with yel¬ 
low and lead-coloured 
markings, due to the de¬ 
velopment of the larva ; The Milkwee d Butterfly (male) drying its 
finally the crown be- wings, after emerging. ' Sketched from life, 
comes dark leaden colour 
from the black head showing through the shell. The egg stage 
lasts only three and three-quarter days (about 90 hours). 
Larva. Directly after hatching from the egg, the larva 
eats almost all the empty shell, leaving only the base. It 
eats away the crown to make its exit. On August 12th at 
