Is the monarch caterpillar dead?
One of our monarchs started pupating and only got a third of the way. It's hanging there with most of the skin still on with a small portion of chrysalis exposed. It's been like this for a couple of days. Is this one dead? I'm wondering if I should remove it in case it was diseased and may affect the other cats I have in my cage.
Sounds like it could be Nuclear polyhedrosis virus. A very common sign of this is failure of the larva to fully pupate. I would carefully remove the caterpillar and make sure and sterilize your equipment as soon as you safely can with a 20% bleach solution.