Now that we're all up to speed on underground etiquette, artist Jay Shells has created a new piece aimed at dog owners. One of these just went up at 14th Street near 8th Avenue, and as you can see it comes with biodegradable bags for the taking. Animal reports that the artist is looking for suggestions on what other dog-stained neighborhoods might be in need of a visual and functional reminder guilt trip. And we're wondering what he should tackle next!