PHYSIOLOGY: P.D.LAMSON 
523 
To obtain uniform results the animals were etherized, and blood 
taken from either the jugular or femoral veins by means of a hypo- 
dermic needle, which method has been shown to give a true index of 
the red count in the generally circulating blood. 
The entire intestine, its mesentery, the omentum, spleen and pan- 
creas were removed singly, and in other cases altogether, after which 
epinephrin was injected. Epinephrin caused the same increase in num- 
ber of red cells in these animals in which the above organs had been 
removed as in normal animals. It is apparent then that these organs 
are not the chief seat of the changes by which the red count is increased. 
As the liver could not be removed except by the introduction of 
mechanical compHcations, its part in the production of polycythaemia 
was sought by other means. 
In the first place animals were completely tied in two above the dia- 
phragm. This is accomplished by opening the chest on both sides 
between two of the lower ribs, cutting the tissues to the sternum and 
back bone, and tying the great vessels, the sternum, back bone and 
adjoining tissues securely with strong ligatures. Except for what blood 
could pass up and down inside the vertebrae, the animal was completely 
tied in two above the diaphragm. 
In such an animal, the injection of epinephrin caused no increase in 
the number of red cells. 
An operation in which the animal was again tied in two, but this 
time placing the ligatures about the aorta just below the mesenteric 
artery and above the renal arteries, and completely tying the rest of the 
vessels and tissues at this level, gives an animal similar to the one above, 
except that the blood supply to the liver, spleen, intestine, mesentery, 
pancreas and omentum has been added. As we know that removal of 
all these organs except the liver, has no effect on the production of poly- 
cythaemia after the injection of epinephrin, we have for our purposes, 
in this case merely added the liver to the animal which was divided 
above the diaphragm. 
Epinephrin injected into such an animal increases the number of red 
cells as in a normal animal. 
From these experiments it appears that the liver is the seat of the 
changes which cause an increase in number of red cells. Further proof 
of this was obtained by quite different means. 
On account of the irregularity with which the hepatic artery branches 
it was considered a more certain means of shutting off the arterial blood 
supply to the liver to ligate the coehac axis artery, than to attempt 
ligation of the hepatic artery. The coeliac axis artery supplies the 
