Katydid

Yesterday, I saw a leaf walking along the side of the house.

It was katydid. I don't know what it was doing on the side of the house, but it had been there for over a day.

I think this is called a "true katydid", aka pterophylla camellifolia.  It likes oak trees and makes a sound that goes "katy did" or "katy didn't," although I didn't hear this one say anything.

They generally are about two inches long; this one had very long antennae.

We used to see these a lot when we were children, but I hadn't seen one in ages. Maybe when you're younger and closer to the ground you see such things better - or maybe they're another one of those species that come and go in cycles, although nothing I've read says anything about that.

The brown part on its back makes me curious, but I am not sure what that is. 

Katydids are kin to crickets and often mistaken for grasshoppers, though they are in the same scientific family as grasshoppers, etc. 

There are about 255 species of katydids in the US alone. They are found all over the world except for Antarctica.