Animal Kingdom Animalia (Animals)

These are glossosomatids, Jason. They are probably Glossosoma nigrior, though it is possible that we are looking at mixed species. The ones to the right with their aggregate of similar sized grains are classic Glossosoma, while the ones to the left with the large anchor pebbles could possibly be Agapetus. Regardless, they're all commonly referred to as saddle case makers.

In this picture: Caddisfly Family Glossosomatidae (Saddle-case Makers).

This isn't really an underwater picture, but a picture taken into my aquarium of midge larvae which lived in the silt I used for substrate. Each larva has a little tower of detritus (Detritus: Small, loose pieces of decaying organic matter underwater.) built up along the bottom, while the bare larva waves around from the top.

In this picture: True Fly Family Chironomidae (Midges).

Here's a view through the stationary den of a type of netspinning caddisfly larva.

In this picture: Insect Order Trichoptera (Caddisflies).

A crayfish munches on an unidentified white thing.

In this picture: Arthropod Order Decapoda (Crayfish).