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.
Platyhelminthes are also known as flatworms because they are worms with a flat body. This is the main external morphological feature that differentiates them from nematodes (roundworms).. The most well-known representatives of platyhelminthes are worms that cause human diseases, such as taenia and schistosome. Planaria, since it has been extensively studied in Biology, is also well-known.