prey digestion in the insectivorous plant sarracenia purpuero was investigated with consideration of three sources of proteolytic enzymes self-digestion by the prey, bacteria in the plant pitcher, and enzymes produced by the plant itself. to do this, 5. purpurea seedlings were grown under sterile conditions and tissue cultures were established. the plant seedlings and tissue culture grew slowly. tests on pitcher fluid in plant pitchers, or artificial pitchers containing water, or pitcher fluid, and with or without a cricket as prey showed that the cricket is a very important source of protease and that without induction of proteolytic activity by captured prey, the pitcher is largely inactive. more research is needed to determine the relative importance of the different sources of protease in the 5. purpurea plant pitcher, particularly pitcher plants grown in sterile conditions will greatly advance this research by permitting investigation of the contribution of the plant pitcher alone.