>The first that came to mind was Platanus acerifolia, the London plane tree, which we in the US call the sycamore. But then, I wondered, if we here call it a sycamore and the English call it a plane tree, how come King James' translators used the expression sycamore tree in the story of Zaccheus?

Yes, all very confusing, Bob. For me, planes and sycamores are quite different trees.

Here in Melbourne, Australia, we have many thousands of what we call plane trees as street trees - they are in fact platanus occidentalis, also known as the American plane or Occidental plane. They are large deciduous trees, and have large leaves, and large round hard furry seed balls.

The sycamore, as we use the term, is acer pseudoplatanus (note that pseudo-plane bit!), and is a member of the maple genus. Also large and deciduous with large leaves, one distinguishing feature is its winged or "helicopter" seeds.

I'm no botanist, but I think that in Australia, and probably in Britain too, plane trees are the genus platanus, and maple trees are the genus acer, and the sycamore for us is just one of the maples. From what I have researched just today, in the US you call all of the genus platanus (our planes) "sycamores" or "buttonwoods", including platanus acerifolia (The London plane); you refer to the genus acer as maples (as we do), and acer pseudoplatanus (our sycamore) you appear to call the "sycamore maple" (that's not too bad) or "planetree maple".

Still with me?

To confuse the picture further, the eastern fig, or mulberry fig, or sycamore fig, ficus sycomorus, is apparently also called "sycamore" by some people or in some parts of the world. Here's a picture of what I believe is that type of tree in Jericho, purportedly that of Zaccheus fame, definitely not the large-leaved maple or plane (check out the second row, first image):
http://www.edwardfudge.com/photoalbum4.html