Mineral Deficiency as a Factor Limiting Growth of the Ciliate Tetrahymena geleii

Abstract

Evidence obtained with "vitamin-free" casein media indicates that the ciliate, T. geleii, requires Ca and Fe for growth. Inorganic salts, as supplements to a deficient basal medium, may be replaced by such organic preparations as yeast-extract, brewer''s yeast and extract of alfalfa meal (either dethiaminized or untreated).