Who were the tribes the Lewis and Clark encountered in North Dakota? Had the Mandan and Hidatsa ever seen an African-American before? How did tribes fare in the wake of the expedition?
The flatworms, flat worms, Platyhelminthes, Plathelminthes, or platyhelminths (from the Greek ÏÎ»Î±ÏÏ, platy, meaning flat and á¼Î»Î¼Î¹Î½Ï (root: á¼Î»Î¼Î¹Î½Î¸-), helminth-, meaning worm) are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates.
These 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. The circulatory system is very crucial for many organisms, but the species in this phylum do no have this specific system.