Or ever, really. I think there was some dinosaur droppings in the first Jurassic Park movie, and poor Plastic Man was forced into a pile of it off-screen in that Dinosaur Island episode of The Brave and the Bold (see, he disguised himself as a shovel to hide from the gorillas and...never mind, it takes too long to explain), but how often do you see a dinosaur in the act of going to the bathroom?
This particular image of this particular thing I you don't see very day was scanned from The Dinosaurs (Bantam Books; 1981) by William Stout, who wrote the introduction to Dark Horse's recent Turok, Son of Stone Vol. 1, and has a new art book coming out soon that I sure wouldn't mind getting a review copy of (hint, hint).
I've been trying to read The Dinosaurs for about two weeks now, but I keep getting distracted by the images, and spending a while looking at and re-looking at them and never actually getting to the words (After a few attempts, I'm only on like page ten). If you like dinosaurs or drawings I'd highly recommend the book, as it's just bursting with fantastic illustrations of dinosaurs and other prehistoric creatures. If I were going to give it an in-depth review or discussion, I would want to scan some images, but narrowing it down to a couple of great ones would be pretty tough, and I'd want to scan about 50 or so.
So I decided to just scan one of a dinosaur going to the bathroom, and making a pretty funny face while it does so. Click on the picture for a better view of what kind of expression a sauropod might have had on its face while relieving itself.