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.
Specific animals that are part of this phylum are: Tapeworms, Flatworms, and also Planarians. So, these worm-like creatures are part of this phylum and do not contain a circulatory system.hese Flatworm creatures are hermaphroditic, which simply means that they have both male and female reproductive organs, and that they are able to produce both sexually and asexually. Now, the creatures of the Platyhelminthes phylum do not contain a body cavity nor a circulatory system.