176 VENOMOUS SNAKES AND THE PHENOMENA OF THEIR VENOMS 
guinea-pig, and had been freed from their native complements by washing. 
The results obtained are closely in parallel. All four of the venoms become 
active upon the addition of a suitable quantity of crotalus complement. The 
hemolytic process is, however, very much slower than in the cases where the 
serums homologous to the corpuscles are added. It was found, again, that 
the velocity of the hemolytic reaction is increased by using larger quantities 
of the venom, in combination with the crotalus complement. From this 
fact Flexner and Noguchi considered it possible to divide the intermediary 
bodies of venom into two groups, namely, the isocomplementophilic and the 
heterocomplementophilic. It appears to be remarkable how far the number 
or amount of the heterocomplementophilic amboceptors exceed the isocom- 
plementophilic in all venoms. From this it at once becomes evident why 
venom in general is so powerfully destructive when introduced in a heterolo- 
gous system, while it has almost no effect upon the homologous blood. 
The behavior of the complement of Pityophis cateniferis is quite different 
from the crotalus complement. With none of the venoms here employed 
did it produce a complete hemolysis even after a very long period of action. 
As the controls underwent more or less complete hemolysis after some hours, 
especially with cobra venom, the addition of the pine-snake complement is 
seen to have acted antihemolytically, at least to a certain extent. There is an 
indication that the complement of this snake is far less suitable in activating 
the venom lysins than that of Crotalus adamanteus. In a subsequent series 
of experiments they found that the crotalus complement can promptly reacti- 
vate the crotalus-serum amboceptors (the serum heated to 56° C.), but only 
partially those of the pityophis blood, and vice versa. 
According to the activability of the venoms by snake complements on one 
hand, and by heterogeneous complements on the other, Flexner and Noguchi 
have shown the relative amounts of the isocomplementophilic and hetero- 
complementophilic intermediary bodies in crotalus, moccasin, copperhead, 
and cobra venoms. In the case of the corpuscles of guinea-pigs, crotalus 
venom contained about 7 times as much of the isocomplementophilic as of 
the heterocomplementophilic intermediary bodies. For the corpuscles of 
dogs, on the other hand, the hetero-body is present in excess in about the 
proportion of 12 to 1. With the other venoms the heterocomplementophilic 
bodies are found to exist in excess in about 60 to roo times. That these figures 
would differ were the native complements available in each case is indicated 
by the distinctly weaker action of pine-snake serum upon crotalus venom 
as compared with its own serum. 
Flexner and Noguchi then took up the question of the haptophore groups 
of the venom-intermediary and serum-intermediary bodies. First the cor- 
puscles of the dog, guinea-pig, and pigeon were subjected to the action of the 
crotalus serum previously heated to 56° C. for 30 minutes in order to abate 
the action of the complement. After contact for a few hours the corpuscles 
were separated by centrifugalization and washed in 0.85 per cent salt solution. 
These corpuscles had fixed the intermediary bodies to themselves, as they 
