The largest Monarch caterpillar did molt overnight, its old skin was still laying next to it in the morning. Got a picture. I have about 8 Monarch caterpillars feeding on one potted tropical milkweed plant in the enclosure now. Two pretty big ones, 3 medium size, 3 tiny ones that just hatched.
The Black Swallowtail caterpillars are also in the enclosure, on some fennel cuttings.
There are many more eggs and small caterpillars on plants in the garden, both Black Swallowtails and Monarchs. Now, if I could only attract some additional species to lay eggs on host plants in my garden!