NEW DISTRIBUTION RECORDS OF AQUATIC OLIGOCHAETA (ANNELIDA) FROM RUNNING WATERS IN ONTARIO

Studies of oligochaetes in invertebrate collections at the Royal Ontar io Museum resulted in new distribution records for several species of freshwater worms. Nearly 300 sites in Ontario rivers and streams were sampled with approximately 3000 specimens examined. Forty-three oligoc haete taxa were identified, mostly naidids and tubificids but also inc luding lumbriculids and one species of haplotaxid. Nais variabilis was the most common worm found, followed by Limnodrilus hoffmeisteri, Sty laria lacustris, Tubifex tubifex, and Chaetogaster limnaei. Specimens of Limnodrilus tortilipenis, previous ly known only from Illinois, wer e found in Ontario.