I tie all my caddis with a CDC body and a deer hair wing, a variation of the CDC and Elk. I learned a couple of lessons when trying to tie some Little Black Caddis. The pattern book told me it was a size 16, so I tied them on standard size 16 dry fly hook and tied them in the proportions, wing about 1.5 times the body length. They didn't work. I laid my fly down on a rock that had a couple of little black caddis and they were a lot smaller than my fly. I caught a couple and measured them when I got home. An the from head to the tip of the wing it was 7 mm long, about the shank length on a standard size 16 dry fly hook. The body was about 3 mm long. Next batch I tied was on a size 20 shrimp/caddis pupae hook, and it ended up being the only caddis pattern where I use a CDC body and a CDC wing.