( 623 ) 
also too late (when it has recovered itself again). I presume that 
Orro has thus been led astray. 
I have still to add here that, if the second toxic injection is applied 
not in the abdomen or subcutaneously, but in the circulation — in 
consequence of which the symptoms of intoxication show themselves 
very soon and pass very quickly — these symptoms may already be 
present even before the alexine has disappeared from the serum of 
the animal. From this may be concluded that the symptoms of 
poisoning are not the consequence of the loss of alexine, but that 
these two are processes running parallel, independent of each other, but 
both having a common cause. And this can be no other but the 
reciprocal influence of the horse-serum administered (the antigen) 
and the reaction-products, specific for this, of the sensitized organism, 
arisen after and in consequence of the first injection of the alien 
serum. 
This being settled, we continue asking ourselves: where are these 
reaction-products to be found — probably a particular kind of anti- 
bodies? Where do we meet with such materials as show a particular 
and specific affinity to horse-serum ? 
In order to answer this question, of course the first thing done 
was to examine the serum of sensitized guinea-pigs, but without 
any special result. For in not a single combination such serum 
gives a precipitate with horse-serum. Another possibility for the 
disappearance of the alexine from the serum of the intoxicated ani- 
mals might still be found in the presence in their circulation of 
antialbuminoid sensibilisators of Guncou. But also these seem to be 
wanting; I have repeatedly been able to convince myself that ana- 
phylactic serum, again in not a single combination with horse serum, 
is able to fix alexine. On the other hand | have been able to prove 
that the serum of the sensitized pigs reacts antialexically with respect 
to fresh horse-serum, and especially during the stage in which after 
the toxic injection the original alexine has disappeared from the 
circulation. Although I now reserve to myself the duty to revert 
to the meaning of this fact on a future occasion, yet it seems to 
me that this formation of antialexines (which we also meet with at 
the usual serum-immunity) does not bring us much nearer to the 
explanation of just the anaphylactic complex of symptoms. 
But if not the fluids, it is perhaps the cells that can bring us a 
step onward? — | have applied to the erythrocytes of the guinea- 
pig, and it has appeared to me that washed normal pig-blood, 
brought in contact with horse-serum, whilst a sufficient quantity of 
physiological solution of sodiumchloride is present, is able to fix 
