NATURAL HISTORY, TORONTO REGION
found in almost any gathering of water. Our only record of the free-living forms is
Cyclops quadricornis—Tap-water (Acheson).
Many are parasitic in habit, attaching themselves to the gills or skin of fishes. They have been studied by Prof. Ramsay Wright.
Ergasilus centrarchidarum Wright—on Perch, Rock Bass and Sunfish (Wright).
Actheres micropteri Wright—Black Bass (Wright). Lernaeopoda edwardsii Olsson—on Brook Trout (Wright).
Argulus stizostethii Kellicott—on Lunge and Rock Bass, Georgian Bay.*
In addition to the well-known earthworms, of which there are no Toronto identifications, a large number of aquatic forms, mostly of small size, are to be found here. Only the following have been noted.
Lumbriculus sp.—Toronto Bay (Nicholson). Saenuris canadensis Nichols.—Toronto Bay (Nicholson).
sp.—Toronto Bay (Nicholson). Chaetogaster langi Bretscher—Aquaria, Biol. Dept. Nais tortuosa Walton—Aquaria, Biol. Dept. Pristina leidyi Smith—Aquaria, Biol. Dept.