BIPHASIC PARTICULATE MEDIA FOR THE CULTURE OF FILTER-FEEDERS.

1. Over 200 parthenogenetic generations of the freshwater Cladocera Moina macrocopa were obtained aseptically in three artificial media. 2. The media have two phases: a liquid phase supplying mineral salts, water soluble vitamins, nucleic acids, and a liver extract and a fine particulate phase made from coagulated proteins, starch and lipid factors. 3. The particulate phase supplies the bulk nutrients very efficiently; hence, this type of media may be useful for growing other filter-feeders.