Your plants are epiphyllums, commonly known as orchid cacti. Your condition
is rather common. While it could be caused by sucking insects, the spots are
more commonly caused by either water left on the plants in full sun causing
sunburn (water drops act as lenses magnifying the light to burn small round
patches), or by overwatering at a time of the year when the temps are lower
and the plant cannot use or get rid of excess water. Epiphyllums are rarely
hit by fungi, at least on the "leaves" (stems). And the most common insect
problem is mealybug which is easily seen. Give your plants a winter rest by
reducing water and fertilizer especially if they're not in full sun or
receiving full natural light, depending on your location. Good growing.
Gary
"Lynn Coffelt" wrote in message
...
Help, something is blistering my orchid cactus leaves. Picture is
posted on alt.binaries.pictures.gardens. I've got two or three varieties
of
something Wife calls "orchid cactus" growing in the greenhouse. One (the
most beautiful when it decides to bloom) has this blight that I can't seem
to slow down. I don't want it to spread into the others until I learn
something about control.
Each little spot seems to start with a little watery blister, and then
dry up into a much harder brown blister. I thought at first it was some
kind
of a bug inside the early stage blister. I popped one or two open and
using
a 10x glass looked for something squirming or with legs...... nothing I
could identify.
Is this ailment something anyone knows about? And also I'm sure that
there is a better name for the plant than "orchid cactus"..... maybe some
help there too!

Thanks in advance!
Lynn (really rank amateur greenhouser)