This picture is of a microscopic view of a macrostomida that I found in some substrate that I had collected from around a lake by the border of NC and SC. The organism was moving around the substrate while I was trying to take a picture of it. I took this photo around 2:00pm.
According to Target Study, they lack a respiratory system, a skeletal system, a circulatory system, and a body cavity. (http://targetstudy.com/nature/animals/platyhelminthes/)