ANALYSIS OF THE BLOOD OF THE VENA PORTA, ETC. 423 
hepatic veins. In clogs, as in horses, the blood of the hepatic 
veins is much richer in blood-globules and extractive matters 
than that of the vena porta. 
I have remarked, in both dogs and horses, that a consider- 
able quantity of iron always disappears from the blood in 
traversing the liver. But the differences in the quantity of 
iron which is found in the blood which enters the liver and 
in that which issues from it, are greater in dogs than in 
horses. It results from this that a portion of the haematine 
of the blood disappears in the liver, and contributes probably 
to the formation of the colouring matter of the bile, wdiich 
would also prove the complete analogy of bilifulvine with 
haematoi’dine, as one of my pupils has just shown. 
COMPARATIVE ANALYSIS OF THE BLOOD OF DIFFERENT 
VEINS WITH ARTERIAL BLOOD. 
All these comparisons were made with blood always taken 
from the same horse. 
The blood which issues from the liver by the hepatic veins 
is ahvays by far the most saccharine blood of the w 7 holebody. 
Aftenvards, this blood is mixed wfith that of the vena cava in 
order to reascend to the heart. I can here only confirm w-hat 
M. C. Bernard said long ago — namely, that the blood of the 
vena cava inferior is that which always contains the greatest 
quantity of sugar next to the hepatic veins. I have found 
in the solid residue of the blood of the vena cava in horses, 
0-346 gr. per cent., 0-211 gr. per cent., and 0-492 per cent, 
of sugar. 
When the blood has traversed the lungs and has become 
arterial, we generally find no sugar. I have found none in 
the arterial blood of horses which had eaten starch and oats. 
In dogs and rabbits, we can only find sugar in the arterial 
blood, w*hen the venous blood contains more than 0 3 gr. per 
cent, of sugar. This is what happens in all the conditions 
wdiich cause sugar to pass into the urine ; for example, after 
the puncture as made by M. Bernard, after the injection of 
sugar in large quantities into the veins or into the stomach, 
or, finally, in rabbits which have eaten considerable quan- 
tities of beetroots or carrots. But, in all these circumstances, 
it is always the hepatic veins which contain the greatest 
quantity of sugar, next the vena cava, & c. 
The blood of the small veins, such as the cephalic vein, the 
digital vein, and the vena abdominalis externa of horses, 
always contains less blood-globules, more serum, and, conse- 
quently, more w ater, than arterial blood. But the larger veins, 
