Okay - disappointing, but not surprising.
Still not sure it's a match. We only have the one picture from him:
"Small tree, green fruits almost identical to those of C. obovata"
... but the descriptions I find of C. arborea say:
"Fruits are three-valved capsules that split open to reveal reddish orange seeds"
"All year round the shrubs produce ornamental red fruits that are persistent on the plant."
Oh, hey, found a picture of C. arborea fruit on the Smithsonian website - yeah, it looks nothing like the picture:
http://biogeodb.stri.si.edu/herbarium/species/?spnumber=2356Also found this, which looks like the Smithsonian pics, and shows the aforementioned three-lobed-splitting behavior:
http://fincaeltigre.blogspot.is/2012/09/wrenching-transition-of-dual-worlds.htmlBut then again... Rare Palm Seeds is selling something that looks pretty similar to Jim's as C. arborea:
https://www.rarepalmseeds.com/pix/CasArb.shtmlAnd Useful Tropical Plants links this Flickr image from C. E. Thomas Paine, which could also be a match:
Meh, IDs are difficult
I'll just assume for now that it's C. arborea, unless Jim decides otherwise.