Part IL 
HORSE SERUM IS POISONOUS TO A ** TREATED ** OR “ USED ” GUINEA PIG. 
It has long been known by some of the manufacturers of diph- 
theria antitoxin that when antidiphtheric serum is inoculated into 
a used guinea pig the result is almost invariably death. By a “used” 
or “ treated” guinea pig we mean one that has recovered from the 
effects of an inoculation of the toxine-anti toxin mixture used in test- 
ing the potency of diphtheria antitoxin. For example: 
G. P. No. 4191. Six c. c. antitoxic horse serum (Alex. 192) injected into the peritoneal 
cavity. Death in 15 minutes. 
[Previous treatment : 26 days prior, inoculated subcutaneously with 0.139 c. c. toxine 
No. 5 + 3 -io c - c - antitoxic horse serum (PD&Co 08033).] 
G. P. No. 4103. Nine c. c. antitoxic horse serum (Alex. 193) injected into the peritoneal 
cavity. Dead in 5 minutes. 
[Previous treatment: 31 days prior, inoculated subcutaneously with 0.22 c. c. toxine 
No. 7 + 2 -q-o c - c * antitoxic horse serum (Alex. 190).] 
G. P. No. 4330. Six c. c. antitoxic horse serum (Natl. VIII. 17) injected into peritoneal 
cavity. Dead in 2 minutes. 
[Previous treatment : 26 days prior, inoculated subcutaneously with 0.139 c. c. toxine 
No. 5 + 2 -^o c. c. antitoxic horse serum (Alex. 185).] 
G. P. No. 6 B. Six c. c. antitoxic horse serum (Natl. VIII. 17) injected into peritoneal 
cavity'. Dead in 27 minutes. 
[Previous treatment: 86 days prior, inoculated subcutaneously ’with 0.22 c. c. toxine 
No. 7+1 unit antitoxic horse serum (Standard B25).] 
G. P. No. 4381. Six c. c. antitoxic horse serum (Natl. VIII. 17) injected into the peritoneal 
cavity. Dead in 10 minutes. 
[Previous treatment: 11 days prior, inoculated subcutaneously with 0.22 c. c. toxine 
No. 7 + 3 -Y 0 c. c. antitoxic horse serum (Natl. V. 10).] 
G. P. No. 4336. Six c. c. antitoxic horse serum (Natl. VIII. 17) injected into the peritoneal 
cavity. Dead in 12 minutes. 
[Previous treatment: 21 days prior, inoculated subcutaneously with 0.139 c. c. toxine 
No. 5 + 3 +g- c. c. antitoxic horse serum (PD&Co 07635).] 
G. P. No. 4369. Six c. c. antitoxic horse serum (Natl. VIII. 17) injected into the peritoneal 
cavity. Symptoms; recovered. 
[Previous treatment : 21 days prior, inoculated subcutaneously with 0.22 c. c. toxine 
No. 7+++ antitoxic horse serum (Cutter 1461).] 
G. P. No. 4377. Six c. c. antitoxic horse serum (Natl. VIII. 17) injected into the peritoneal 
cavity. Symptoms; recovered. 
[Previous treatment: 21 days prior, inoculated subcutaneously with 0.22 c. c. toxine 
No. 7 + 3 +- c - c - antitoxic horse serum (Natl. V. 7).] 
( 11 ) 
