﻿STUDIES IN PLAGUE IMMUNITY. 



249 



Table No. IV. — Foreign Scrum Number II and normal monkey serum — Agglutination 



tests January 17. 



FOREIGN SERUM NUMBER II. 



Dilutions. 



After 1 

 hour. 



After U 

 hours. 



After 2 hours. 



After 21 hours. 



Virulent 

 strain. 



1:2 



1:10 



Control. 

 1 :2 



Negative _ 

 do 



Slight pre- 

 cipitate. 

 do __ _ 



Distinct pre- 

 cipitate. 

 do 



Marked precipitate. Fluid not 



entirely clear. 

 Very heavy precipitate. Fluid 



'cleared. 

 Negative. 

 Heavy precipitate. Fluid 



cleared. 

 Do. 



■ Do. 



do .... 

 do ... 



Positive ._ 



Negative ___ 

 Positive 



Negative 



A virulent 1 

 strain. ] 1:10 

 I Control. 



do .... 





Negative . 



. .do 









NORMAL MONKEY SERUM. 



Virulent 

 strain. 



Avirulent 

 < 

 strain. 



1:2 

 1:10 



Control. 

 1:2 



1:10 



Control. 



Negative . 

 . do _ _ 



Negative 



__do. — 



Negative 



Bacteria be- 

 ginning to 

 sediment. 

 Negative 



Negative. 



Heavy precipitate. Fluid not 

 entirely clear. 



Negative. 



Moderate precipitate. Fluid 

 not clear. 



Heavy precipitate. Fluid en- 

 tirely cleared. 

 Do. 



do____ 



do 





.do- 







do - 















From the above experiments we can conclude only that the precipitate of the 

 bacteria is coarser grained and that it occurs somewhat earlier in the immune 

 serum than in the normal monkey serum. 



Table No. V. — Foreign Serum Number II and immune monkey serum — Agglutination 



tests January IS. 



FOREIGN SERUM NUMBER II. 



Dilutions. 



After li hours. 



After 2 hours. 



After 5 hours. 



Maassen 



i 

 strain. 



Virulent 

 strain. 



1:2 

 1:10 

 1:20 



Control. 



Control. 

 1:10 



Control. 



Negative 



Negative _ — 



Negative. 



Do. 

 Positive weak. 

 Negative. 



Do. 



Do. 



Do. 



_ _ do 



_ __do. 



do 



.. do 



Sediment beginning to form 

 Negative _ . 



._-do 



_ „do ___ _ _ 



- do — 



_.. - do — _ - __ 



.._..do 



-do 





IMMUNE MONKEY SERUM. 



Maassen 

 strain. 



Virulent 

 strain. 



1:2 



1:10 



1:20 



Control. 



. Control. 



1:10 



. Control . 



Negative ._ 



Negative - .- 



Negative. 

 Positive. 



Do. 

 Negative. 



Do. 

 After 5 hours.* 

 Negative. 



_ .do 



Positive* 



... do 



-do.* 



do 



do 





do .. 



do 



do- 



do 



do . 







*A sedimentation is occurring and particles are collecting in the fluid, strongly simulating aggluti- 

 nation. 



