Jellett et al. (1989) recently published a note on the field occurrence of the pathogenic amoeba responsible for sea urchin mass mortalities in Nova Scotia during the early 1980's. Their conclusions could have benefitted from more thorough research. The following are specific points of concern. The title ('Non-occurrence of free-living Paran~oeba jnvadens in water and sediments of Halifax Harbour, Nova Scotia, Canada'), the abstract ('Seawater and sediment samples from various sites in or near

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... alifax Harbour were cultured for Paramoeba. .'), and the purpose ( ' . . . t o determine . if P. invadens can be recovered from sediment or seawater. .') all refer to sediment sampling in Halifax Harbour. However, the only sediment sampling mentioned in the methods or results was from an aquarium in the laboratory.