The utilization of paramecia by the carnivorous plant Utricularia gibba.

A method has been devised to ensure capture of large numbers of live paramecia within a short period of time under controlled conditions by the bladders of Utricularia gibba. The method permits a direct evaluation of the role of entrapped animals in the nutrition of this carnivorous plant. Paramecia captured by the bladders of plants growing in a near optimal inorganic medium do not cause an increase in number or length of internodes. In contrast, feeding paramecia to plants grown in a poorly balanced or incomplete medium does result in an increase in both number and length of internodes produced. Feeding paramecia to Utricularia also results in an increase in number of bladders.