The variety of flatworms and their medical significance.

So, if we talk specifically about medical significance, then only representatives of two classes of classes have it, in fact, these are Sosalschik and Tape.
It is worth knowing that absolutely all flatworms are three-layered. Also, these creatures have a so-called skin-muscle sac. It is worth knowing that these creatures can live in an aquatic environment (and in a salty one) and on the ground. It should be noted that about twenty-five thousand species of these creatures have been described for the current period of time.