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.
The name Platyhelminthes means flat worms; there are about 15,000 living species. They live in marine and fresh water habitats, moist terrestrial environments, and inside other organisms as parasites. All have. : ectoderm on the outside, endoderm lining the gut, and mesoderm in between.he name Platyhelminthes means flat worms; there are about 15,000 living species. They live in marine and fresh water habitats, moist terrestrial environments, and inside other organisms as parasites. All have. : ectoderm on the outside, endoderm lining the gut, and mesoderm in between.