This year we searched our milkweed plants and found some monarch caterpillars on them. We brought four inside (this was on the 19th) and put them in a "critter carrier" plastic tank with lid, similar to these, but longer, along with a nice supply of milkweed.
Unfortunately, something happened to the first caterpillar--after turning into the chrysalis, something made a cut in the casing, and there was extra silk hanging from it. Could have been an insect brought in on the milkweed, maybe. I ended up removing it when this other caterpillar changed into a chrysalis.
We soon had two more turn into chrysalises, but the second caterpillar that made the "J" died before reaching that point. It just hung upside down, straight, again with silk hanging down. So right now we have just two chrysalises.
And one quickly growing caterpillar. This is the same one from 9 days ago.
And yes, you're seeing frass scattered on the bottom of the tank. The larger the catties get, the larger the frass. I had to empty the tank after the others were "done."