I got the answer from another group. Take a look at the Photo's section
under Friends of Hewlett.

--- In adogsbreakfastfans@yahoogroups.com, "kindred1964"
<kindred1964@...> wrote:
>
> During the "A Dog's Breakfast" scene where Marilyn and Ryan are
talking
> in bed, Ryan has a tattoo on his right shoulder. Yet during
> the "Starcrossed" episode, Colt did not have a tattoo. So who has a
> tattoo? Ryan or Paul McGillion? Regardless, does anyone know what the
> tattoo is of?
>