Ha! Marble belly button! I like it. It's fitting.
The glass does come out in a stream, and sometimes you will have creases at the ends of the stream. The ends ideally are pressed smoothly into the glass but sometimes things are too cool and they don't get smoothed over entirely.
Not sure if that's what you're getting at.
No "pontils" on these Jabos. Possibly what someone might call a "cutline" at the end of the glass stream.