31 
G P. No. 195. Four c. c. antitoxic horse serum (Natl. IX. 17) injected into the peritoneal 
cavity. Symptoms. 
[Previous treatment: 55 days prior, inoculated subcutaneously with gio c - c - ca t 
serum.] 
1 day later 6 c. c. cat serum injected into the peritoneal cavity. Dead in 35 minutes. 
Rat serum. 
G. P. No. 168. Six c. c. antitoxic horse serum (Natl. IX. 17) injected into the peritoneal 
cavity. No symptoms. , 
[Previous treatment: 34 days prior inoculated subcutaneously with c - c - r( R 
serum.] 
2 hours later 2 c. c. rat serum injected into the peritoneal cavity. Severe symptoms. 
Dead in 3 hours. 
We infer from the above series that guinea pigs treated with the 
serums of various animals and subsequently injected are much more 
susceptible to homologous serums than to heterologous serums. We 
have here another indication that this toxic action of blood serum is 
quantitatively specific. 
We expect to take up the work with the serums of other animals 
more in detail, and the results will be reported at another time. 
THE RELATION OF HEMOLYSIS. 
So much work has recently been done indicating that the toxic 
property of blood serum is closety allied with its hemolytic action 
that we made some experiments in order to determine what connec- 
tion exists between the hemolytic and toxic action of horse serum 
upon guinea pigs. As a result of these studies we believe that we 
have shown very clearly that blood serum may contain an acute 
poison entirely independent of any hemolytic action. 
Landois a in his work on transfusion showed long ago (1875) that 
the blood serum of many mammals dissolves the red blood cells 
of other mammals. Landois specifically demonstrated that the red 
blood corpuscles of rabbits, when mixed with alien blood serum, are 
readily dissolved, while, on the other hand, the red blood corpuscles 
of cats and dogs are much more resistant. If large quantities of red 
blood corpuscles are dissolved, there follows an excretion of hemo- 
globin through the kidneys, intestines, and also into the serous cavi- 
ties. If the serum is injected into the blood stream of a rabbit, 
some of the erythrocytes of the rabbit are dissolved in vivo, as 
may readily be confirmed microscopically; but before the corpuscles 
are dissolved there is an agglutination of the blood corpuscles into 
clumps, by means of which large capillary areas may become plugged. 
The same process is seen by the further extraction of hemoglobin 
from the mass of the stroma of the corpuscles which fills the capil- 
a Landois: Lehrbuch der Physiologie des Menschen, 1896. Die Transfusion des Blutes. 
Leipzig, 1875. 
