IO20 THE AMERICAN NATURALIST. [Vor. XXXV. 
dissolves the erythrocytes of animals from all other classes. 
of vertebrates, and also of other birds. 
The results of the experiments with sera of mammals agree 
entirely with the results of Landois's experiments with trans- 
fusions, but they do not agree with the results obtained by 
Ehrlich and Morgenroth, Bordet, and Gürber. This lack of 
agreement is doubtless due to difference in methods. The 
investigators named above washed out by isotonic salt solution 
all the serum from the erythrocytes of one animal and added 
large quantities of the erythrocytes to the serum of another 
animal. By this method in many cases no globulicidal action 
can be observed, while, if a small quantity of simply. defibri- 
nated blood be added to the serum, the erythrocytes are quickly 
dissolved. The importance of adding only small quantities of 
blood to the serum lies in the fact, observed by Buchner, that 
in the mingling of two different sera the globulicidal action may 
be either increased or diminished. In transfusion experiments 
the more blood injected the better. 
The carotid arteries of a cat and an ocelot were connected 
so that an exchange of blood took place from one animal to the 
other. After a short time the blood of each animal was sup- 
posably well mingled with that of the other. No hemoglobin 
appeared in the bladder of either animal. The blood of the 
cat and of the ocelot is physiologically equivalent. If a cat and 
a rabbit be connected in the same way, both animals die in a 
few minutes from the poisonous effects of the foreign blood 
upon the central nervous system. Death occurs before any 
globulicidal action takes place. Two rabbits connected in this 
way exhibit no pathological symptoms. 
The experiments upon mammals lead to the conclusion that 
among animals of the same family there are no marked differ- 
ences in blood ; but the blood of animals of different suborders 
is not physiologically equivalent, while the blood of animals of 
different orders exhibits very marked mutual globulicidal action. 
The blood of the mouse and blood of the rat are mutually inac- 
tive. The blood of the hare and of the rabbit is equivalent ; 
but rabbit serum dissolves corpuscles of the guinea-pig, and 
rabbit corpuscles are dissolved by serum of the guinea-pig, 
