Both are Dizygotheca elegantissima.

As for why the larger one is losing leaves, it could be either too much or two little water. If it helps, not only are 3/4 of mine at home dropping a lot of leaves now, but most of the ones we've got at work are as well. My suspicion is that it's probably too wet: that's definitely the problem with mine and the work ones.

The plant might benefit from being moved slightly away from the corner: air movement is supposed to be important to them (this also fits with the problems I've been having with mine). They are also said to tolerate cold temperatures reasonably well, but not hot so much, so if it's in the path of a heat vent, that could be causing a little bit of the problem too. (I don't really have any personal experience one way or the other on that point.) My growers' guide also says that ethylene (sometimes an impurity in natural gas) can cause leaf drop, so if it's near a natural gas source, you might try to minimize exposure there.

You should also check the plant carefully to rule out spider mites or mealybugs, both of which find Dizygotheca especially tasty, but you probably knew that.

The growers' guide also suggests that leaf drop is a natural thing as plants mature, and not necessarily anything to be alarmed about: brighter light is said to reduce the problem there but won't eliminate it entirely.

My overall guess is that it's probably just too wet, either because of an overly-helpful husband or because it's using less water as the days get shorter, and it will eventually level out again. I assure you that I do feel your pain (though your plants are both much larger than mine, so I probably don't feel it as much). You'll probably have to watch the moisture level a little more closely than you're used to for a few months, but I'd be surprised if the two (or three, I guess, if we include your husband) of you couldn't reach some kind of satisfactory agreement fairly soon.

Pam, both your Dizy's are gorgeous..Were the pics taken after or before leaves dropped? If after, I could only imagine what it looked like prior leaf drop..
Tell your dh not to water your plants..sometimes we have to be firm so they get the message through their thick skulls..LOL.
An east window should be sufficient..My plant book says, any light one can read by is adequate. I guess that depends on someone's vision, but I'm assuming they're referring to med-bright light.
Check the soil by sticking your finger as far as it'll go..does it feel wet? dry?
I let most plants dry between waterings, but give the Dizy a 'tad' more water than other tropicals.
Of course this is up to you, but I firmly believe daily misting and once a wk hosing helps..Hosing in sink or shower increases humidity, cleans leaves, and reduces mite attacks.

Mr Sub...Maybe you can answer a question about a Dizy I too got at Walmart, though nowhere near as nice as Pams.
Got it in Sept..You mention both Dizy's as being one and the same??? I know they're in the same family, but thought they were differnet species..no? Anyway, the one I bought came in a 4" plastic pot..the mystery is, (it was the only Dizy growing this way) but the plant grows both types of foliage..some are long and narrow and the other is longer, thicker, there's no center stripe down the middle..What's up w/this plant? Thanks and Happy Holidays, Toni

As far as I know, there aren't even any cultivars of Dizygotheca elegantissima*: I've seen the variegated-looking plants before but haven't had the opportunity to check closely to see if they were in fact variegated or just having the tiniest amount of marginal leaf burn.

I'm not sure about the both-kinds-of-foliage question; I can't really picture what you mean. It's possible that your plant came from a cutting of mature foliage (the mature leaves are broader, less lacy-looking: the grower's guide compares them to a brown Fatsia japonica), though I'd be surprised if that's what's happened. The only thing described in the growers' guide is that there's a pesticide that will cause the plant to grow very narrow, "strappy" leaves, but the pesticide in question isn't labeled for use on Dizygotheca anymore, so if that's the cause then somebody's been doing something illegal. It could just be that the plant has experienced changes in growing conditions, and the leaves have changed too.

*(In fact, technically, there isn't even any Dizygotheca elegantissima: it's been renamed to Schefflera elegantissima. On this particular plant, though, I'm unwilling to yield to the march of scientific progress. The older name was better and more fun to say.)

Mr. S and Toni - thanks so much for your speedy replies!

I think you're right about the overwatering, and after cross-examining my better half, I've realized that yes, the fact that the days are now much shorter and it's getting watered at the same rate, is probably what's causing it. Heat vent - hmmm. It's close - about 3 ft from one in the floor so it might be getting a bit more heat than it's had before.

Toni, yes, the pic was taken last night, when I looked with horror and saw that one stem had only about 4 leaves left on it! When it was new, it was truly amazing, so bushy it almost looked artificial.

Mr. S, I so agree with you about the name change. My plants will always be "dizzy Gothics" - I've got teens in the house who have been both dizzy AND goth at various stages of their sweet young lives... and they think I'm making the name up! It's good for a laugh and yes, they love saying it.

Thanks again! Will report back...