Here's another pic

Caterpillars?

Well mine did the same a couple months ago. Do you grow inside? Or was it inside earlier this summer? I was told fungus. I got sulfur for plants at box store. I put it in a shaker and sprinkled it on affected leaves. It stopped the fungus! I cut off the worst leaves. I believe the fungus is actually called "rust".

Mine were inside because we were on vacation. The air conditioning was off and the air movement was non existent. So conditions were right!

But your holes in he plant appear to be a caterpillar or cut worm. Look around for the guy. A cut worm was on my moms orange tree! And it made similar holes in the leaves!

Hope that helps!

I don't care about the holes. It's the white stuff I'm worried about. I know slugs, snails, earwigs, and every other bug under the sun love to eat these plants. I want to know what the WHITE STUFF is.

You want to know, do you? Get rid of the critters, and the white stuff won't be there - it looks to me to be an epidermal reaction to the leaf being chewed on.

Sorry I guess I didn't explain very well. The white stuff is what appears to be the fungus. Sulfur is sold in powder form to cure fungus. Epiphyllum are notorious for it if there is lack of air movement and hot humid conditions exist.

t,

Isn't that just what their native conditions are?

Yes they are hot and humid in natural environment. Mine was inside and NO air movement for 12 days. Someone turned the air completely off :(. After sulfur and moved outside mine is back to growing and no fungus.

I googled white fungus on plants and saw similar looking stuff. I have no idea about epidermal reaction. And hopefully wont!