Phylum Platyhelminthes; Class Turbellaria (Flatworms
Courtesy of the Cacapon InstituteSoft-elongated body flattened from top to bottom; no individual segments; digestive track with only one opening which functions both as the mouth and anus; mouth usually on the bottom side positioned about one-fifth to the length of the body; sides of the body  constricted towards the front forming a head that is often somewhat triangular shaped; two eyespots situated on top of the head gives the animal a cross-eyed appearance.  Most families can withstand high nutrient and organic enrichment, but some are very sensitive to toxics. Crawler/burrower; Collector/gatherer; VS-L (H)(S/F)