VENOM HMOLYSIS AND VENOM AGGLUTINATION 179 
The toxoid formation of hemolytic principles, first observed by Myerswith 
the cobra venom, has been confirmed by Flexner and Noguchi with the Ameri- 
can venoms. They did not find such rapid deterioration as was mentioned 
by Myers. They found that hydrochloric acid in the concentration of 2 to 
3 per cent caused only a slight deterioration of heemolysins after 48 hours. 
Lamb (1903) estimated the hemolytic value of cobra venom for a number 
of the bloods of different animals by using the calorimetric measurement in 
small test-tubes containing a known quantity and the red corpuscles in 
question. He brought out no specially new point as to its behavior upon the 
red cells, but he has shown that 1 per cent solution of cobra venom resists 
the heating to 73°C. much better than o.1 per cent solution of the same venom. 
With unheated venom 0.005 c.c. of the blood suspended in 0.5 c.c. isotonic 
salt solution was dissolved by 0.015 mg. ‘lhe heating of 1 per cent solution 
of the venom raised this minimal complete hemolytic dose to 0.0312 mg., 
while that of o.1 per cent solution was raised to 0.25 mg. 
Now, coming to the hemolytic property of the daboia venom, Lamb found 
a somewhat singular phenomenon, namely, that this venom, while a powerful 
destroyer of the red corpuscles im vivo, did not readily dissolve the blood 
corpuscles when the cells were directly mixed with the venom in a saline 
solution in vitro. This fact has also been observed by Cunningham and 
emphasized especially by Stephens and Myers. Lamb found that in order 
to start hemolysis of any kind of blood it was necessary to have the toxicity 
of the saline medium somewhat below the isotoxicity, so as to produce a par- 
tial destruction of the corpuscles before the venom is introduced, recollecting 
also that Stephens and Myers noticed that the addition of the normal horse 
serum accelerated the hemolysis with this venom. 
Weir Mitchell’s phenomenon, namely, non-hemolysis by too strong a con- 
centration of venom, has also been observed with the daboia venom in vitro. 
As to the resistance of the hemolytic principle of the daboia venom, Lamb 
finds that it differs from that of the cobra venom, as the former loses its activ- 
ity completely when heated to 73° C. in a o.1 per cent solution, whereas only a 
certain diminution of power takes place in the latter venom. Another point 
of difference between these two venoms is the far more powerful hemolytic 
action im vivo possessed by the daboia venom. 
Noc, working with a large variety of snake venoms, established the fact 
that the phylogenetic relation between the main families and genera of poi- 
sonous snakes is not merely an anatomical and morphological factor, but 
also a biological factor, for he found that the activity of the hemolytic prin- 
ciples of their venoms obeys the linear course and rank to which each snake 
is assigned in the natural system. Noc’s experimental data bearing on this 
point are simple. He determined the length of time required by 1 mg. of 
each venom to hemolyze completely 1 c.c. of 5 per cent suspension of the 
washed corpuscles of horse in 0.9 per cent salt solution in the presence of 
0.2 c.c. of the normal horse serum heated previously to 58°C. It was neces- 
sary to add this amount of the heated horse serum to obtain hemolysis, as 
