172 VENOMOUS SNAKES AND THE PHENOMENA OF THEIR VENOMS 
a brilliant contribution to our knowledge of the nature of venom hemolysis. 
As will be seen below, Kyes, in his first article, confirmed the observations of 
Flexner and Noguchi as well as those of Calmette and explained at the same 
time the apparent discrepancies existing between the results obtained by 
these investigators. He found that there are two kinds of blood corpuscles, 
according to their susceptibility to the hemolytic action of snake venom — 
cobra venom being chiefly employed: (1) the corpuscles which undergo 
hemolysis by venom without a second substance; (2) the corpuscles which 
become hemolyzed only when auxiliary substances (complements, etc.) are 
present at the same time. The corpuscles of guinea-pigs, dogs, and man 
were found to be most susceptible, and those of rabbits and horses quite 
resistant, while those of the ox, sheep, and goat were completely refractory to 
the cobralysin. 1 c.c. of 5 per cent suspension of the first-named corpuscles 
is hamolyzed by only 0.25 c.c. of o.or per cent venom solution, while those 
of the horse are dissolved by 1 c.c. of 0.1 per cent concentration, requiring 
nearly 40 times more venom than in the case of corpuscles of dogs or guinea- 
pigs. Kyes found that the insusceptible kinds of corpuscles can be dissolved 
by venom if certain suitable fresh serums be introduced. ‘Thus he gives the 
following combinations as corresponding with the examples of amboceptor- 
complement-like phenomenon of venom hemolysis: Ox corpuscles, guinea- 
pig serum; sheep corpuscles, guinea-pig serum; rabbit corpuscles, guinea-pig 
serum; horse corpuscles, ox serum. ‘The complementing property of guinea- 
pig serum is seen to disappear by heating to 56° C. for 30 minutes. He was 
also able to confirm that the cobra amboceptors are absorbed by sheep cor- 
puscles at o° C., even in the presence of guinea-pig serum. 
After having confirmed the facts described by Flexner and Noguchi in cer 
tain particular instances, Kyes now proceeded to clear up the phenomenon 
why certain kinds of corpuscles are attacked by venom directly. It was found 
that the susceptible corpuscles contain in their constituents certain substances 
capable of activating cobra venom. ‘This group of ‘‘activators”’ was called 
endocomplement and found to be thermolabile. From the ox corpuscles 
he was able to obtain active endocomplement, notwithstanding these cor- 
puscles are entirely insusceptible to the cobralysin in their integrity. This 
phenomenon was explained by assuming that the endocomplement of this 
kind of corpuscles exists in an unavailable state, but becomes accessible after 
their disintegration, through which process endocomplement was prepared. 
Returning to Calmette’s phenomenon, namely, the acquisition of venom- 
complementing property of various serums, irrespective of whether one was 
incapable of activating venom in its fresh state or not, after heating to a tem- 
perature above 62° C., Kyes found that heating all kinds of blood serums to 
too° C. invariably renders them activating for cobra venom, and, indeed, 
more active in this respect than in an unheated native state. Finally Kyes 
discovered that the thermostabile venom activator of blood serum can be 
