37 



it has more often belonged to types Pn. 42 and Pn. 26 than to any- 

 one other. This may mean no more than that these two are 

 common types in the pharynx, but there is not at present 

 sufficient evidence to decide whether this must be accepted as the 

 explanation. 



Case l.—Pn. 112. 



The material was the sputum from a man aged 45 years, and was 

 taken on the sixth day from the onset of pneumonia (a crisis had not 

 occurred). A mouse inoculated with the sputum died on the following 

 day : the peritoneal washing, which contained a variety of organisms, 

 was tested with the type sera and gave a slight positive reaction with 

 Type I. The blood of the mouse was plated and six pneumococcus 

 colonies were subcultivated. These were tested in whole broth cultures 

 with the type sera. One colony culture reacted with Type I serum, two 

 with Pn. 26 serum, one with Pn. 42 serum, and one with Pn. 87 serum. 

 Thus, four distinct serological races were present in the sputum. 



Case 2.—Pn. 118. 



The sputum was from a boy aged 10 years, and was taken on the fourth 

 day of pneumonia. The peritoneal washing from the inoculated mouse 

 gave a Type I reaction, and eight colony cultures grown from the mouse's 

 blood all reacted with Type I serum. 



A second specimen was taken 13 days later, that is, 11 days after the 

 crisis. The sputum was plated directly and eight pneumococcus colonies 

 were tested with the type sera. Three colonies were Type I, two were 

 Pn. 42 type, and three did not react with any of the sera. A mouse died 

 after inoculation with the sputum, and its blood was plated : five colonies 

 were tested, of which two were Pn. 42 type and three did not react with 

 any of the sera. Type I was not obtained through the mouse. 



A third specimen was taken 19 days after the crisis, on the 27th day 

 of the disease. Twelve pneumococcus colonies, grown direct from the 

 sputum, did not react with any of the sera. From the blood of the mouse 

 inoculated with the sputum, 21 colony cultures were made : fourteen of 

 these were Type I, three were Pn. 42 type, and four were negative to all 

 the sera. 



Case 3.— Pn. 106. 



Sputum from a case of pneumonia on the fourth day of the disease 

 (pre-critical) was inoculated into a mouse. The peritoneal washing from 

 the infected mouse gave a reaction with Type II serum. 



A second specimen of sputum was taken three weeks later. Five 

 colonies were grown direct from the sputum, four of which were Type II, 

 and one was Pn. 42 type. The blood of the inoculated mouse was plated, and 

 16 colonies were tested : 14 belonged to Type II and two were Pn. 42 

 type. 



Case 4.— Pn. 125. 



A specimen of sputum from lobar pneumonia in a man aged 18 years 

 was taken before the crisis. A mouse was inoculated, and 13 colonies were 

 grown from the blood. Seven reacted to Type I serum, five to Pn. 26 

 serum and one was negative with all the sera. 



Case 5.— Pn. 67. 



Sputum from a case of pneumonia on the eighth day of the disease in 

 a man aged 44 years was inoculated into a mouse : the peritoneal washing 

 reacted with Type I serum. 



A second specimen of sputum was examined 16 days later during a 

 relapse : a mouse was inoculated and its peritoneal washing reacted with 

 Type III serum. A second mouse was inoculated with the dried spleen 

 of the first mouse and on its death its blood was plated. Five pneumo- 

 coccus colonies were tested, two of which reacted with Type III serum 

 and three with Pn. 42 type. 



x 17680 B 3 



