1909.] Intracellular Constituents of Bacteria, etc. 331 



by the leucocytes than when the serum is undiluted, and this applies to the 

 serum both of the inoculated, and of the uninoculated, animals. 



Table II. — Effects of Dilution on Staphylococcus Vaccine and Endotoxin 

 Sera. Number of Cocci ingested by 50 Polymorphonuclear Leucocytes. 



Period. 



Dilution 



of 

 serum. 



Control 

 (opsonic index 

 = !)• 



Vaccine 

 serum 

 (1 c.c. vaccine). 



Opsonic 

 index. 



Endotoxin 

 serum 

 (O'l mgrm.). 



Opsonic 

 index. 



Control 



undiluted 



210 



235 



1 -1 



199 



0-95 



before 



1 in 5 



335 



356 



1 -06 



315 



0-94 



inoculation 



1 10 



432 



410 



0-95 



397 



0-92 



24 hours 



undiluted 



233 



183 



0-8 



400 



1-3 



after 



lin 5 



286 



• 256 



9 



241 



0-85 



inoculation 



1 10 



295 



190 



-64 



214 



0-7 





1 20 



108 



121 



1 -1 



144 



1-3 



48 h jurs 



undiluted 



85 



131 



1 -5 



326 



3-8 



after 



1 in 10 



100 



169 



1-7 



358 



3 6 



inoculation 















72 hours 



undiluted 



58 



92 



1 -6 



156 



2-7 



after 



1 in 10 



80 



133 



1 -66 



131 



1 -6 



inoculation 















6 days 



undiluted 



125 



186 



1 -5 



306 



2-4 



after 



1 in 10 



185 



211 



1 -14 



365 



2-0 



inoculation 















12 days 



undiluted 



102 



131 



1 -3 



177 



1-75 



after 















inoculation 















(See Note at end of Table I.) 



C. Bacillus tuberculosis. — Two preparations of tubercle endotoxin were 

 used, one prepared from untreated tubercle bacilli, the other prepared from 

 tubercle bacilli previously extracted with ether. The effect produced by the 

 endotoxins was compared with that produced by a small dose of German 

 Tuberculin E. The results obtained are charted graphically in Chart V of 

 the opsonic indexes. 



From Chart V it will be seen that the German Tuberculin E (dose 

 0'002 milligramme) produced little effect (Eabbit X). A corresponding dose 

 of tubercle endotoxin (prepared with unextractecl bacilli), on the other hand, 

 induced a marked and prolonged rise in the opsonic index, which was 

 preceded by a slight negative phase (Eabbit XI). A relatively huge dose of 

 the same endotoxin (1 milligramme) produced a decided negative phase 

 followed by a rise in the opsonic index of approximately the same amount as 

 that produced by the smaller dose (Eabbit XII). A similar dose (1 milli- 

 gramme) of the endotoxin prepared with ether-extracted tubercle bacilli 



