Varicose veins are large, raised, swollen blood vessels that twist and turn. They usually develop in the legs and can be seen through the skin. Spider veins are smaller, red, purple, and blue vessels that also twist and turn. Spider veins are easily visible through the skin, as well.
Common name: Flatworms. 1  Scientific name: many species. Phylum: Platyhelminthes. 2  Description: Although they are called Flatworms, these invertebrates are not flat. They are round-bodied with a flat belly. 3  Fun facts: A Flatworm has a single opening to its stomach, in the middle of its underside.
Planaria is the common name of freshwater, non-parasitic flat worms found in may parts of North America and Europe. These flatworms are three to twelve millimeters long. The Dugesia Tigrina is brownish in color. Some of the worms have a stripe down their back. It has a large mouth in the middle of its body.