The Filter-Feeding of Artemia

Abstract

1. The rates of filtration and of ingestion have been studied in Artemia of different ages feeding on pure cultures of plant cells of three different species, the concentrations of cells being varied over two orders of magnitude. 2. The animal is capable of regulating its rate of feeding in such a way that, as the cell concentration increases, the filtration rate maintains a constant maximum value while the ingestion rate increases. When the concentration reaches a value at which a constant maximum ingestion rate is attained, the filtration rate falls off. 3. In older animals the maximum ingestion rate is reached at a lower cell concentration than in younger animals. 4. The maximum filtration rate is independent of cell size. The maximum ingestion rate is inversely related to cell size, the total volume of cells ingested being the same for three species of plant cells. 5. The means whereby the animal maintains a maximum rate of total volume of cells ingested per unit time, irrespective of their size, has been investigated and is discussed.