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.* 



ANNELIDA. 

 Oligochaeta. 



In addition to the well-known earthworms, oi 

 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 (Nich- 

 olson). 



" sp. Toronto Bay (Nicholson). 

 Chaetogaster langi Bretscher Aquaria, Biol. Dept. 

 Nais tortuosa Walton Aquaria, Biol. Dept. 

 Pristina leidyi Smith Aquaria, Biol. Dept. 

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