792 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
The classification might be represented by the following scheme 
/ Sozins : — 
Defensive proteids present in 
the normal animal. 
Phylaxins 
Defensive proteids present in 
the animal after it has been 
k made artificially immune. 
r Myco-sozins : — 
I Alkaline globulins from rat (Hankin), 
/ destroying anthrax bacillus. 
\ Toxo-sozins 
I Of rabbit, destroying the V. Metchnikovi 
v poison (Gamaleia). 
Myco-phylaxins : — 
Of rabbit, destroying pig typhoid 
bacillus (Emmerich). 
Toxo-phylaxins : — 
Of rabbit, &c., destroying diphtheria 
and tetanus poisons (Behring and 
Kitasato, antitoxin of Tizzoni and 
< Cattanf). 
Prof. Emmerich read a paper on “ The Artificial Production of 
Immunity against Croupous Pneumonia and the Cure of this Disease.” 
He stated that his previous experiments on swine fever had proved that 
in immune animals the bacilli of swine fever were destroyed, not 
by the cells of the animal, but by a bactericidal substance present in 
the blood. It had been clearly proved by his experiments that the 
bacilli of swine fever were destroyed almost immediately after their 
introduction under an immune animal’s skin. Applying these researches 
to the disease produced in rabbits by the inoculation of the Diplococcus 
pneumoniae of Fraenkel, he showed that non-immune rabbits died within 
twenty-four to forty-eight hours after the introduction of the virus. 
But if such animals had been previously treated with the blood or serum 
of animals rendered artificially immune against the diplococcus of 
Fraenkel, such animals did not die, but recovered after the introduction 
of extremely virulent diplococci. Moreover, when the Diplococcus pneu- 
moniae was inoculated into an animal, it was possible to cure it by 
injecting shortly afterwards some of the serum of an animal rendered 
artificially immune. In the blood of animals rendered artificially im- 
mune against pneumonia we possessed an excellent cure for the disease. 
Not only would it be possible to cure men afflicted with pneumonia by 
these injections, but we could, by preventive inoculations applied in time, 
put a stop to the spread of an epidemic in a school or a prison for 
instance. His experiments, together with Dr. Doenissen’s, had a great 
practical as well as a theoretical value. 
Dr. Ehrlich stated that he had lately made a number of experiments 
with ricin which threw great light on the question of immunity. 
According to Kobert and Stillmark, ricin was an extremely poisonous 
body, for it acted fatally when such small doses as 0*03 mg. were 
injected into an animal’s veins. When absorbed through the alimen- 
tary canal, a dose one hundred times larger could be easily tolerated. 
Nevertheless, even then, it was so toxic that, according to Kobert’s 
reckoning, a dose of 0*18 gr. would prove fatal to a full-grown man. It 
had a harmful influence on the blood, producing coagulation of the red 
blood-corpuscles, and thromboses, more especially of the vessels of the 
alimentary canal. 
In his opinion the toxicity of ricin greatly depended on the species 
of animals used for experiments, the animals most susceptible to its 
