Abstract
Surface-active polyoxy-ethylene ethers (Triton) had little effect against tubercle bacilli in vitro, but were strongly active against the organisms in vivo. The tubercle bacilli grew slowly or not at all in monocytes derived from animals treated with Triton, while the same bacilli grew freely in monocytes from untreated animals. The action of Triton is probably indirect, since its addition to a culture of monocytes from untreated animals had no action against intracellular tubercle bacilli.