54 
Philippine Journal of Science 
1920 
Days of the experiment. 
Fig. 1. Growth curves for dogs fed on fresh and autoclaved milk. Note the falling off of 
growth between the tw'enty-seventh and the thirty-first day. Note also that dog 2, 
which was not infected with Ascaris, continued to grow at about the normal i-ate. 
The paper of Schwartz represents the most recent contribution 
to this subject that is accessible to us. Among the other con- 
clusions he has drawn from his experiments are the following: 
The failure to demonstrate hemolytic principles in the excretions of the 
worms when kept in vitro appears to favor the view that hemotoxic sub- 
stances of ascaris partake of the nature of endotoxins. There is also 
to be considered the possibility that the death of a woi-m in the intestine 
may be follov/ed by a rapid disintegration of its tissues and the liberation 
of toxic substances befoi’e it passes out of the body of the host. Tallquist, 
in fact, has shown that in the case of another parasite (Dibothriocephalus 
laius) that the toxic substances are liberated only when the worm disin- 
tegrates, which affords a possible explanation why Dibothriocephalus some- 
times produces no ill effects on its host, whereas in other instances a 
severe anemia is present. The fact that in some cases human beings and 
other animals infested with ascarids remain in apparent good health 
while in other cases they show evidences of suffering from such infesta- 
tion may perhaps be explained in much the same way as the differences 
observed in cases of infestation with Dibothriocephalus. 
Further on Schwartz adds: 
The above observations [evidence as to the mechanical attack of Ascaris 
upon the mucosa and the ingestion of blood], coupled with the presence 
of oxyhemoglobin in the worms, a substance which apparently is constantly 
being excreted by the parasites (to judge from their behavior in vitro) 
