Most mushrooms change their appearance, some dramatically, as they go through their life cycle. This can make them difficult to identify because most field guides only show them at the peak of maturity. Shaggy Mane mushrooms grow quickly, open into a bell shape, and then turn black. They are not poisonous.
This is also a Pinnularia, but a different species. It is an “empty” diatom; meaning that it has died and all of its inner features have disappeared. This makes the details of the frustule much more visible. Many amateur microscopists treat diatoms with harsh acids to dissolve their inner workings for this reason. Acid does not harm the frustule, which is virtually indestructible.
Diatoms are probably my favorite single-celled micro-organisms. They can photosynthesize and are often quite mobile. Diatoms are a type of algae that has a glass-like outer shell (frustule) that can be very ornate. Note the outer edges of this sample (Genus: Pinnularia) – the most common genus in our vernal pond.
A vernal pond is a small temporary body of water which usually makes its brief appearance in the springtime. This is a local one that I use as a source of micro-organisms. The number of micro-critters is relatively high but the variety is not so great. This is because the only permanent residents are those which can withstand repeated de-hydration and re-hydration as the pond comes and goes throughout the year.