It has been suggested that poliomyelitis virus given intravenously is excreted along the area supplied by the olfactory nerve1 and that Macacus rhesus monkeys thus inoculated contract the disease because the virus is reabsorbed by the end fibers of the first and thirteenth nerves, the virus being then carried to the central nervous system along the nerve fibers. It seems logical to suppose that after the virus is injected intravenously it is excreted not only along the region derived from the stomodeum, i. e., the nasal area, but also along the gastrointestinal tract. Instillation of a 1 per cent solution of zinc sulfate in the nasal area prevents poliomyelitis from occurring in experimental animals if the virus is subsequently introduced by way of the nose. If the virus is excreted only by the nasal route after being intravenously injected, zinc sulfate should prevent the disease in animals thus inoculated.