There is one Monarch butterfly caterpillar at J stage. Two more appear to be affixing to the Alstroemeria to prepare for J stage.
This J stage is the stage right before the caterpillar sheds its skin and becomes a chrysalis.
I’m trying to catch that shedding, but it’s difficult to do without a time-lapse camera taking photos every 5 minutes or so. But with three caterpillars in- or headed-to-J stage, maybe I’ll get lucky.
This is a fascinating process. If you want to see more, search for “Monarch Butterfly Lifecycle” on YouTube, there are many amateur videos which show the process from J stage to chrysalis.