Houseguest

I found him in a bag of lettuce given to me from a friend's garden. I brought the lettuce home on Monday and washed it several times in the sink, but he eluded detection. I felt bad that he was in my fridge for a week and hardly moving, but a couple of hours in the sun and a little lettuce has perked him right up. You can see the big hole he's eaten in one of the leaves (there are three more). Can anyone tell me what he is, and where I should put him when he has fully recuperated? I would like to give him a nice home in a tree, as I don't think apartment living is for him.



For the time being, his name is Walker. For obvious reasons. :)