Two Monarch chrysalises
The caterpillar's body becomes a "soupy" mix of cells while it is in the chrysalis. During the 10 - 14 days that it is pupating, the caterpillar goes through a marvelous transformation. As the cells rearrange, wings slowly begin to show through the transparent shell of the chrysalis, a different kind of mouth is forming and the butterfly will soon develop scales and begin to turn black. The last 24 hours are the most amazing to watch as the chrysalis quickly turns from green to black and orange.
Note the black line and the small gold dots on the green chrysalis. Some scientists believe they may help function in camouflage. The butterfly in the black chrysalis emerged a couple of hours after this photo was taken. The green one emerged a few days later.