Species not observed since 2000 are maked *
  PORIFERA (Sponges)
SPONGILLIDAE:
  River Sponge.* Ephydatia fluviatilis (Linnaeus)
Formerly encrusting stones in streams
 flowing through Area V.
  CNIDARIA  (Hydra)
HYDROIDA.
HYDRIDAE:
  Green Hydra.* Hydra viridissima (Pallas)
Contained in water samples from the Newt Pond (A).
  Brown Hydra.* Hydra oligactis (Pallas)
Contained in water samples from the Newt Pond (A).
PLATYHELMINTHES (Flatworms)
TRICLADIDA.
PLANARIIDAE:
  Flatworm.* Polycelis nigra (Müller)
Found under stones in main stream.
  Flatworm.* Polycelus felina (Dalyell)
Found under stones in main stream.
  ROTIFERA (Rotifers)
  Wheel Animal.* (Species not determined).
Contained in water samples from the Newt Pond (A).
TARDIGRADA (Tardigrades, Water-bears)
(Species not determined).
ANNELIDA (Segmented Worms)
CHAETOPODA. (Earthworms)
  Earthworm Lumbricus sp.
  Earthworm.* Allolobophora sp.
  Potworm.* Mesenchytraeus sp.
HIRUDINEA. (Leeches)
 
  Leech. (Species not determined).