Go find...

your own leaf - this is mine and you're not having it - or at least that's what the message the ( bottom) caterpillar seemed to be giving to the other smaller one above -( just like children not wanting to share.)  It was actually getting quite aggressive and continuously swinging at the smaller one's head.  It did eventually move away.  Lots of caterpillars demolishing the swan plants very quickly now - just a few reserve plants left which should enable quite a lot to get to maturity.  
Thank you to the wonderful admirer for hosting Silly Saturday.