What was one joke that was mentioned in the reading?

From the text:

Lieutenant Cross nodded and closed his eyes while the others clapped Strunk on the back and made jokes about rising from the dead. Worms, Rat Kiley said. Right out of the grave. Fuckin' zombie.

Three times a day, no matter what, I had to stop whatever I was doing. I had to go find a private place and drop my pants and smear on this antibacterial ointment. The stuff left stains on the seat of my trousers, big yellow splotches, and so naturally there were some jokes. There was one about rear guard duty. There was another one about hemorrhoids and how I had trouble putting the past behind me. The others weren't quite so funny.