﻿192 



STRONG. 



Series 23 — Continued. 



CONTROLS. 



Animal 

 No. 



Inoculated De- 

 cember 4 subcu- 

 taneously with — 



Infected 



December 18 



with— 



Result. 



Autopsy and remarks. 



1594 



1595 

 1596 



1597 



1598 

 1599 

 1600 



1601 



1602 

 1603 

 1604 



1605 





Nearly i oese 

 "Pest Viru- 

 lent." 

 do 



Alive and well .__ 

 __ do__ 



Pest bubo with innumerable 

 baciili. 

 Do. 

 Do. 

 Pest bubo with innumerable 

 bacilli. Innumerable bacilli 

 in the spleen. 

 Do. 



Do. 



No evidence of pest infection. 



Pest bubo containing numerous 

 pest bacilli. No organisms 

 seen in a smear from spleen. 







do _ _ 



. .. do . 





do 



Dead Dec. 25, 

 after 7 days, 

 do 





.do 





.do 



_ _ do 





.do 



do 





____ do 



Dead Dec. 26, 

 after 8 days. 



Alive and well 



Dead Jan. 3 



Dead Dec. 27, 

 after 9 days. 



Alive and well ___ 





do _ - 





do _. .. 





do 





do _ 







*It is possible that these animals were suffering with a latent or chronic form of pest at the time 

 of the second reinoculation, although they were apparently healthy. 



The majority of the monkeys of this series, including the controls, were very 

 large, weighing 5,000 grams and over, the large animals having been collected 

 and saved for inoculation in the same series. A number of the controls, as will 

 be seen from an examination of the table, did not die, and hence the exact value 

 of the immunization is not shown by the experiments. In the series of inocula- 

 tions performed after this date, whenever the monkey's weight was over 3,000 

 grams, § oese of "Pest Virulent" was employed in testing the immunity, in 

 place of § oese. However, some of the very large monkeys were apparently as 

 susceptible to pest infection as certain of the small ones. The series on the 

 other hand shows very distinctly an important fact, naniely, that it is not 

 possible to immunize all animals of this species with a single uniform dose, for, 

 although the primary inoculation was so large that it killed some of the animals 

 of this series, in other instances it failed to protect them against the subsequent 

 inoculation of even less than i oese of "Pest Virulent," which amount, in even 

 some of the control animals, did not give rise to a fatal infection. The animals 

 that succumbed to the first inoculation also demonstrate the inefneaey of a single 

 heating in attenuating the pest bacillus, the few bacilli remaining alive in the 

 suspension having retained their full virulence. 



Series 25. — Killed agar cultures of "Pest Virulent" with monkeys. 



On December 8, twenty-eight 48-hour agar slant cultures of "Pest Virulent" 

 (from guinea pig number 1514, second transplant) were suspended in 28 cubic 

 centimeters of 0.085 saline solution (1 cubic centimeter to each culture) and the 

 suspension placed at 05° C. for one hour. Cultures from this suspension after- 

 wards proved to be sterile. Monkeys numbered 1558 to 1571 inclusive were 



