Case 141 stands alone as representing a class in which S. hemolyticus was implanted upon a pneumococcus pneumonia during its course. In this instance two throat cultures on alternate days after the onset of the pneumonia were negative for hemolytic streptococci. Unfortunately the last record of a throat culture is for one taken ten days before the fatal termination of the case, and it can only be stated that the S. hemolyticus infection was implanted within the last ten days of the course of the pneumonia, perhaps on or about October 12 when bilateral otitis media developed. In Cases 285 and 730 hemolytic streptococci were found in the throats five and six days respectively before the onset of pneumonia. They represent the 2 cases of pneumonia which developed in patients isolated in the streptococcus “carrier” ward. Case 285 is of particular interest for several reasons. It is the only case of lobar pneumonia in the group and happens also to be the only case from which B. influenzæ was not obtained. S. hemolyticus was found only once on throat culture, i.e., five days before the onset of the pneumonia. Three throat cultures after the onset of the pneumonia were negative. The case ran the course of a lobar pneumonia. Eleven days after the onset (November 9) a small amount of pleural fluid was diagnosed. Aspirated fluid on this date and again four days later showed many streptococci in smears and pure cultures of S. hemolyticus. The remaining 6 cases belong to a group in which hemolytic streptococci were first identified in the throats after the cases had been reported to the laboratory as pneumonia suspects to be examined by culture before transfer from the measles ward. In all these cases the culture taken at this time was positive while all cultures taken before were negative. In some cases, _e. g._, Cases 98, 147, and 281, throat cultures taken only one or two days before the onset of the pneumonia were negative. In these cases the onset of the pneumonia and the appearance of the streptococcus in the throats appear to be simultaneous. It should be noted that the period between the appearance of the hemolytic streptococci in the throat and the development of the pneumonia is very short in all cases. In this small group of cases S. hemolyticus infection which has complicated pneumonia has been acquired at or near the time of onset of the pneumonia.