Likely a Dalyelliid (such as Microdalyellia and Gieysztoria), with "caudal adhesive papillae" (those little lobes at the end of the tail). If the oval bodies are eggs, as I suspect, that might help rule out some genera (I believe eggs are distributed like this in some Dalyellida).
Unfortunately, I don't know enough about microturbellaria, to rule out Macrostomum....

Great pictures, though!
