Unknown Green Caterpillar

Unknown Green Caterpillar

Observation - Unknown Green Caterpillar. Description: I found this caterpillar munching it's way through an iris plant back in the summer, in my garden. I have tried to identify it, but without success.

I found this caterpillar munching it's way through an iris plant back in the summer, in my garden. I have tried to identify it, but without success.