1. Cryptococci in brain, lung, and abdominar wall and growth of the cryptococcus at 370 is evidence of pathogenicity. Proof of pathogenicity is obtained by intraperitoneal inoculation of white mice or rats. It should be remembered that six months may be necessary for the animals to die and at necropsy the characteristic gelatinous granulomata should be sought and the fungus identified microscopically. The other components of the cerebrospinal fluid are abnormal, and the biochemical pattern may resemble that found in other meningitides, particularly tuberculous meningitis. Sugar is reduced (Wilson and Duryea, 1951) and may fall as low as 5 mg. %; chlorides are lowered (Wilson and;true,1951