Regenerative capacity of the planarian Girardia tigrina and the snail Helix lucorum exposed to microgravity during an orbital flight on board the International Space Station.
Dokl Biol Sci. 2008 Jul-Aug;421:244-7. No abstract available.
Ford notes that:
It's unfortunate that this paper has no abstract and is published in a russian journal that I don't have access to (and presumably, is written in russian). The people outside the eastern bloc just aren't going to be able to know the answer to this pressing question...yet.