The great susceptibility of the representatives of the bird family Fringillidae for the psittacosis virus has previously1 been emphasized. In the course of systematic studies relative to the various birds which might possibly serve as hosts for the virus, a series of white crowned (Zonotrichia leucophrys gambeli) and golden crowned sparrows (Zonotrichia coronata) were injected intraperitoneally with 0.3 to 0.5 cc. of a 10% organ suspension in broth of a mouse or Java bird—passage virus (mouse M.L.D. 10-8). Many of the injected sparrows, which as a rule died in from 8 to 12 days, revealed at autopsy a diffuse plastic exudate teeming with free and intracellular Levinthal-Cole-Lillie bodies. The exudate covered both the pericardium and abdominal viscera. Victoria blue 4 R. was particularly useful to demonstrate the free elementary bodies. The liver necroses and the splenic tumor so commonly observed in the representatives of the Psittacidae and some of the Java birds infected with the psittacosis virus were ...