Last Fall my attention was called to an adult Necturus maculosus Raf. in our vivarium by Dr. C. L. Parmenter, in charge, from the cloaca of which protruded some mature tapeworm segments. One cestode only was found in the duodenum which measured 83 mm. The head was easily recovered. It proved to be Ophiotænia lönnbergii (Fuhrmann) as described and illustrated by La Rue (1914). La Rue has frequently found the species in Necturus from Ohio and Indiana. This one is from Allegheny in Pennsylvania, showing a wider distribution. La Rue states: “I have examined your slides of Ophiotænia from Necturus and find them to be O.lōnnbergii without question.”