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Fig. 21. Distribution and abundance of subclass Oligochaeta in the Nee Soon drainage. Solid 
circles indicate sites where representatives were collected and circle sizes are proportionate to 
abundance/numbers of individuals captured as reflected in the accompanying legend. 
Subclass Oligochaeta 
Oligochaeta contains the familiar terrestrial earthworms as well as more obscure 
annelids which live in freshwater habitats. They are distributed throughout the entire 
Nee Soon drainage (being found in 24 sites in total), and are typically found in relatively 
small numbers (1-12 individuals at 22 sites) (Fig. 21). However, large numbers of 
Oligochaeta, 22 and 50 individuals, were recorded at sites 25 and 29 respectively. 
