Green caterpillars and poo/eggs?

lookingforlotte

Hello everyone, does anybody know what type of caterpillar this is that I've found on my lettuce? And whether the dark blobs are eggs or poo?! For some reason they don't seem to be interested in lollo rosso, only the green varieties. They seem to be mostly at the base of the leaves and there doesn't appear to be much damage given the number of them I found and how big they are! 🤷‍♀️

Dovefromabove

The blobs are poo ...  likely to be from the green caterpillars.   It'll wash off.    

Busy-Lizzie

I think they are Cabbage White caterpillars and that is their poo.

Athelas

Also called ‘frass’

lookingforlotte

Thank you everyone!