904. VENOMOUS SNAKES AND THE PHENOMENA OF THEIR VENOMS 
Flexner and Noguchi found that the cytolytic principles of snake venom 
are still active after moist heating to 85° C. for 30 minutes and are not de- 
stroyed by moist heat at a temperature of 100° C. maintained for 15 minutes. 
Dry heating for 2 hours at 140° C. suffices to diminish, but not to abolish, the 
activity of daboia venom. 
The mechanism of venom cytolysis was also studied. They found that 
previous heating of susceptible somatic cells and nerve cells to 55° C. for 
30 minutes renders the cells almost insusceptible to the solvent action of 
venom, although agglutination and some granulation of the cells may occur. 
Addition of fresh serum or fresh body fluid to the mixture of the heated cells 
and venom causes a certain amount of dissolution and disintegration, which 
are never so strong as in the case of unheated cells. Repeated washings of 
the fresh cells in sea-water or saline solution do not suffice to prevent or even 
delay considerable solution of the cells by venom. They also pointed out 
that the cytolysis can not be due to the action of proteolytic ferment of venom, 
for the latter directly attacks the gelatin and is completely destroyed by 80° C. 
In an extensive series of experiments these investigators were able to show 
that venom contains a number of cytolysins, each having a special preference 
for one given group of cells. They also consider that cytolysins of one group 
attack their corresponding cells with varying severity according to the source 
of the cells, which fact they regard as due to the differences in the receptor 
apparatus of similar cells in different species of animals. 
Since the appearance of the above work of Flexner and Noguchi, the 
important discovery by Kyes of the interaction between venom and lecithin 
has appeared and makes it probable that the mechanism of venom cytolysis, 
especially the dissolution of egg cells, may have some resemblance to the 
venom-lecithin hemolysis. As is shown by Jacques Loeb and others, the 
membrane of ova seems to be of a lipoidal nature and the deutoplasma 
contains a considerable amount of lecithin. There may be, at least in part, 
certain relation between the lecithinophilic property and the ovolytic processes 
in this case. Loeb and others have shown that artificial parthenogenesis can 
be accomplished by the combined effects of fat-solvent or fatty acids and 
changes in the toxicity of the medium in which the ova are placed — in the 
presence of oxygen. I have made an attempt to produce a similar phenome- 
non by substituting fat-solvents with weak venom solutions, but so far with- 
out definite result. It is significant that Flexner and Noguchi observed the 
accelerating influence of weak venom solution upon blastula formation. 
In this connection the interesting observations of Féré* on the influence 
of venom upon the evolution of chicken embryos must not be overlooked. 
This biologist introduced the venom of viper (in dose of 0.00005 gm. per egg) 
into the egg-white and found that 83 out of too toxicated eggs presented vari- 
ous anomalies of development when opened and examined 72 hours after the 
inoculation. 
1Féré. Evolution de ’embryon de poule. Influence de l’introduction du venin dans l’albumen de 
Poeuf de poule. C. R. de la Soc. Biol., 1896. IIme Série, 8. 
