This from Rod Tuloss for use of the scope on the following observation. I think it is appropriate for any in this section, and possibly others.
http://mushroomobserver.org/81206?q=8jyp
If you do, then you could first check the stem to seem if it is typical Amanita tissue. The best way to do this is to make some very thin slices of the interior flesh of the stem (cutting with the grain…i.e., along the stipe, top to bottom or bottom to top). Place the thinnest slice you have (about a cm long piece of it) on a microscope slide. If the material is fresh go to the next step; if not, place a drop of KOH solution or water on your slice and cover the material and slide under a small bowl or a petri dish lid or something of that ilk to get the trapped air very humid. After a few minutes remove the cover and soak up the drop of water to make the next step easier.
NEXT STEP: Using a pair of needles (or two things with fine points, anyway) tear the your nice neat, thin slice into fibers and spread the fibers out a bit. The more patience you have with this step, the better the results. Stain with Congo Red or some other cell wall stain. Dilute KOH or water will be good for a mounting liquid. Put on your coverslip and …
NEXT STEP: Observer at about 400X (anyway, “high dry”) because the things you’re looking for are too big for you to use oil immersion.
WHAT ARE YOU LOOKING FOR: The characteristic cells of the stem in the Amanitaceae are shaped like narrow bladders or baseball bats. The size varies from species to species. The length varies from, say, about 100 micrometers to 600 or more micrometers. The cells are narrow in some species and somewhat broad in others. There are a lot of them when you are not looking at tissue very close to the outer surface of the stem. The cells are packed tightly together unless you are lucky enough to have displaced some of them with your needles (that’s what you were trying to do when you were tearing with the needles). The inflated cells are all aligned longitudinally in the tissue (the regular hyphae that are present are aligned the same way).
The process … and the SEEING … takes a little getting used to because the cell walls are thin and your cutting instrument and your needles are going to rip the heck out of a lot of the cells…unavoidably. Take your time.
The cells you are looking for are called “acrophysalides” (“physal” is from the Greek word for bladder). Because of their alignment in the tissue, the tissue of the stem in the Amanitaceae is called “longitudinally acrophysalidic.” It is a defining morphological character of the family. If you don’t have them you don’t have a specimen of the Amanitaceae. If you do have them, then you do have a specimen of the Amanitaceae.
This is not a trade secret. Mistakes in placing species in Amanita or Limacella when they don’t belong there could have been avoided by checking the tissue that I just described. Notice that you don’t have to measure anything. You just need to look…and know what to look for.
Very best,
Rod
