THE DYSENTERY BACILLUS. 



221 



chloroform given, and the lower part of the chest and upper part of the abdomen 

 shaved. The aspirating needle was passed through the abdominal wall just to the 

 left of the ensiform cartilage and about 0.25 centimeter above the tij>, and upward 

 until the impulse of the heart wall was felt against it, when a slight thrust pushed 

 the tip into the cavity of the left ventricle ( sometimes apparently the right ) . 

 By now producing a very slight vacuum in the tube, the blood begins to flow 

 freely into the tube. In this way 20 to 25 cubic centimeters of blood could bo 

 obtained from a rabbit without any apparent inconvenience to the animal. The 

 operation was repeated the next day and the next, and the serum from the three 

 bleedings was then mixed. I readily secured 20 to 30 cubic centimeters of clear 

 serum from each rabbit and the animals are alive and well six months after the 

 bleeding. The serum is always sterile, as it is never exposed to the air until it 

 is to be poured off the clot. 



The macroscopic method as given by Martini and Lentz was followed very 

 closely in carrying out the agglutination tests. The salient points are: (1) Use 

 24-hour agar cultures, suspended in salt solution; (2) the same loop is always 

 employed for scraping off the culture; (3) 1 cubic centimeter of the serum 

 dilution and one loop of the culture are always taken; (4) agglutination takes 

 place at room temperature (about 27° to 30° in this climate); (5) a test is 

 made as to whether the agglutination is true or false by giving the tube several 

 (5) short jerks while holding it by the top. My readings were taken at the end 

 of sixteen hours. 



The following tables give the results of the agglutination tests. For 

 the sake of brevity^ tables of only two of tlie non-dysenteric sera are 

 given, although all were tested and the other four had as little action 

 on the dysentery strains as did the two tabulated. 



Table I. 



Culture. 



Is agglutinated by — 



a 

 o 



o 



tc 

 +.» 



i 



"3 



a 



o 



Normal rab- 

 bit serum in 

 a dilution 

 of- 



Rabbit serum "P. S. II" in a dilution of — 



O 





o 



T-l 



o 



rH 

 r-i 







o 



o 



o 



s 



CO 



T-i 





8 



i 





O 



o 



oo 



rH 



O 



o 



OS 



r-i 



P. S. I 



P. S. II 



S.S.I 



S. S. II 



P. A. I 



P. A. II 



S. A. I 



S. A. II 



L. I 



— 



± 







+ 

 -t- 

 + 

 + 



4z 



+ 

 + 

 + 

 + 



+ 

 + 

 + 

 + 



a- 



+ 

 + 

 + 



+ 



-f 

 -f 



-1- 

 -1- 

 + 

 ± 





— 











— - 



— 



"- 





— 



— 



— 















— 



— 



































































— 



— - 



± 



- 











































L. II 



L. Ill 



L. IV 



L. V 



























































± 



— 



4; 



— 











































L. VI 



























































