The black internal organs inside the river mussel can be eaten after squeezing them out.

C is the gills of the river clam: between the thin skirt and the thick clam meat, there are two and a half pieces wrapped in the clam meat, crescent-shaped, soft, with gill-like texture inside. To be removed.

D is the intestine: next to the gills, it is tube-shaped and contains black sediment. One end is connected to the mussel body and cut off. The other end is glued to the columnar ax foot and torn off.

River mussels are the collective name for a class of animals belonging to the family Mussels (scientific name: Unionidae) of the phylum Mollusca. They are called mussel shells or crooked clams in some places. They live half-buried at the bottom of freshwater lakes, swamps, rivers, etc. In the mud. The meat is edible and can also be used as bait for fish and poultry and as feed for poultry and livestock.

In some areas, freshwater pearl clams are used to raise pearls. The main species used to raise pearls are the triangular sail clam and the ruffled crown clam. The inlet and outlet pipes at the rear end of the mussel body are exposed, and water can flow into and out of the mantle cavity, thereby completing functions such as ingestion, respiration, and excretion of feces and metabolites, filtering microorganisms and organic matter particles in the water, and eating small microorganisms.