I was blessed recently to observe these caterpillars go into their chrysali, not once but twice. On the second occasion, I was smart enough to grab my camera and get some up close pics. =)
A caterpillar begins the process by first working on the web that will anchor his chrysalis to the branch (or in this case, the ceiling) that he will hang from. It looks like they are sleeping, they are so still during this time. One night I sat and watched a little guy for over an hour (and people wonder how I keep my sanity with 5 children!), and he barely moved the entire time. My eyes were nearly crossing, but eventually I was able to perceive his minute movements! After they have spun the web, they turn and grab on with their hind feet, check the web again, and after what seemed like forever for me--they finally let go and drop and hang in a "J" formation. This phase is even longer. I have observed caterpillars hanging in this format for nearly 24 hours before. During that time I have noticed a slight color change...They start to appear green beneath the skin.
At an unannounced time, the caterpillar begins to wiggle (much more perceptible!) and squeeze its muscles--contracting and expanding, and slowly the "J" straightens out.
During this time, literally faster than my digital camera can take a picture then get ready for the next picture, the skin at the back of the "head" splits open and as the caterpillar wriggles, the skin works its way free of the chrysalis underneath.
This was so neat for me to actually observe. Before this, I wrongly believed that the caterpillar spun its chrysalis around it. And I also wrongly believed that it took hours. Once it started straightening out its "J", the whole process only took about 10 minutes.
As the skin wriggles to the top, the caterpillar has to do some mid-air acrobatics in order to not drop to the ground. You see, the feet that he is hanging on to the web with are attached to the skin that he is wriggling off! As the skin gets precariously close to the top, it exposes the chrysalid, which is the small stem-like black thing that you see at the top of the chrysalis in the photos next to the one that is forming. The chrysalid, when viewed under a microscope, has hundreds of barbed edges--reminds me of hook sided velcro. The caterpillar wiggles violently to simultaneously get that chrysalid permanently embedded in the web and to flick off the skin. If he were to fall, he would be killed as the caterpillar at this point is basically a fluid sac.
Just think that the Awesome God that we serve also transforms us from the inside out! It is not always easy, but every monarch butterfly that I see is a great reminder for me that the end results of that process are worth it!