Chart 4.—Shows the time interval between the onset of measles and the onset of the subsequent pneumonia in the 56 cases of pneumonia following measles at Camp Pike. Each case is represented by one of the small blocks measured along the ordinate. The onset of measles in all cases is represented by the line at the extreme left of the chart. The onset of pneumonia in each case is indicated by the limit of the block marked off in days to the right of this line. ] (_a_) =Streptococcus Pneumonias.=—Nine cases of streptococcus pneumonia developed. Of the 867 cases of measles studied, 242 showed throat cultures positive for the hemolytic streptococci at some period of their stay in the hospital. It appears then that 3.7 per cent of the patients carrying hemolytic streptococci in their throats developed streptococcus pneumonia. Thirty-seven cases had positive throat cultures when first observed on admission to the measles wards. It is significant to note that not a single case of pneumonia of any kind developed among these cases. MEASLES PNEUMONIA; STREPTOCOCCUS GROUP Case 98, O. McN. Onset of measles, Sep. 19; admitted to hospital Sep. 21; onset of bronchopneumonia, Oct. 21; of empyema, Oct. 23. Recovered from pneumonia; convalescent in empyema ward. _Bacteriology._—1. Throat culture for: (_a_) S. hem.: Sep. 21, −; 28, −; Oct. 9, −; 20, −; 23, +; Nov. 2, −; 9, −; 15, −; (_b_) B. influenzæ: Sep. 21, +; 28, −; Oct. 9, +. 2. Pleural fluid (culture) S. hem. Oct. 23, +. Case 141, J. G. G. Autopsy No. 438. Onset of measles, Sep. 28; admitted to hospital, Oct. 1; onset of bronchopneumonia, Oct. 6; of otitis media (bilateral), Oct. 12; died, Oct. 18. _Bacteriology._—1. Throat culture for: (_a_) S. hem., Oct. 2, −; 6, −; 8, −; (_b_) B. influenzæ, Oct. 2, −; 6, +; 8, +. 2. Autopsy cultures: Heart blood, negative; left lung, Pneumococcus II atypical, B. influenzæ and S. viridans; right lung, S. hem. and B. influenzæ; right bronchus, S. hem. and B. influenzæ. Case 147, S. W. Autopsy No. 442. Onset of measles, Oct. 1; admitted to hospital, Oct. 2; onset of bronchopneumonia, Oct. 17, with chill and rapid development; died, Oct. 18. _Bacteriology._—1. Throat culture for: (_a_) S. hem., Oct 2, −; 9 −; 15, −; 18, +; (_b_) B. influenzæ, Oct. 2, −; 9, −; 15, −; 18, −. 2. Autopsy cultures: Heart blood, S. hem.; right main bronchus, S. hem. and B. influenzæ. Case 281, T. M. Onset of measles, Oct. 6; admitted to hospital Oct. 9; onset of bronchopneumonia, Oct. 21; of empyema, Oct. 23; recovered from pneumonia; convalescent in empyema ward. _Bacteriology._—1. Throat culture for: (_a_) S. hem., Oct. 10, −; 20, −; 24, +; Nov. 2, +; 9, +; 15, +; (_b_) B. influenzæ, Oct. 10, −; 20, +. 2. Culture from pleural fluid, Oct. 23, S. hem.