My 20 Imperial Moth cats are now 30 days old. They are quite large now, the biggest ones are around 3 1/4". I think they still have a little way to go comparing them with pics I've seen of cats ready to pupate. They are not quite fat enough. This past week some of them have started to develop white/ivory colored spiracles, where before they were the same color as their skin. I'm guessing this happens at a certain instar, yet some of them are much smaller then others when it happened to them. They have been very interesting cats to watch grow and change. Here's hoping I get to see some of them emerge as beautiful moths next year! I can only get one pic to post at a time.

Cathy