Simple valve gear

Jon,
At first look, I thought it was Stevenson Gear. On the Chautauqua Belle, they have the elliptical's inside the engine room, not on the shaft where boats like the Delta Queen and the Minne have them. Looking closer here, it seems to have a different set-up. Sorry for no help, but I too would like to see the correct answer.

Matt & Jon,

From the looks of it that is a Stevenson Gear, slightly modified/simplified, differences look like there is only one eccentric rode, also looks like it is a pair shaped unit to change motion in the eccentric, which I imagine would be fine for a light operation such as this, but I'd imagine this would cause an extensive amount of friction if used under working conditions.

Jon take a look here Practical marine engineering for ... - Google Books for some more information on marine engineering

I suspect it is a non-reversing valve gear, unless the cams are a slip fit on their shafts. Since this is a display model, non-reversing is quite possible.
S'
David D.

I agree with David that it's non-reversing. It also looks to have no provision to vary the length of admission. From these standpoints, I would characterize it as no proper valve gear at all: only a cam driven by a tumbler bar, with a fixed link to the slide valve.