THE BLOOD. 175 



and in solids generally. The cells are also partly flocculent, easily 

 distorted, and soon become jagged after their removal from the 

 body, are richer in hsematine and poorer in globuline, and contain 

 twice as much fat. The intercellular fluid contains a less quantity 

 of a fatty fibrine ; while the serum contains less solid constituents 

 generally (especially albumen), but more fat and extractive matters 

 and more salts than any other vessel. Biliary substances have not 

 been found in portal blood, and sugar only seldom occurs. 



2. The blood of the hepatic vein differs much from that of any 

 other vessel. Compared with the portal vein, it is poor in water ; 

 as 3 to 4 during digestion, and as 5 to 12 after it. Its clot is volu- 

 minous, and easily falls to pieces ; and it contains less serum, in the 

 proportion of 15 to 34. It is far richer in both cytoid and colored 

 corpuscles, the former presenting every variety of size and form, 

 and the latter forming heaps of a purplish-red color. The cell- walls 

 of the latter are also less easily destroyed than those of the blood 

 generally (p. 163), and the proportional amount of moist blood-cells 

 in the blood of the hepatic and the portal veins is as 317 to 141. 

 The latter are, however, poorer in fat and richer in salts, and espe- 

 cially poor in hsematine, or at least in iron (two-thirds as much as 

 in the vena portae), but somewhat richer in extractive matters. 

 Still, they have a greater specific gravity, though lighter in relation 

 to the serum, since the intercellular fluid is far more dense, and con- 

 tains much more of the solid constituents (as 11.8 to 8.4). The 

 latter is, however, either wholly deficient in fibrine, or only con- 

 tains a scarcely perceptible trace of it ; and contains less albumen 1 

 and fat, and much less salts, with considerably more extractive 

 matter, including sugar. 



3. The blood of the splenic vein has been analyzed in horses by 

 Mr. Gray. 2 Compared with that of the jugular vein, it contains 

 more water, iron and fat, and more albumen and fibrine. There is 

 also less solid residue in the serum, which always presents a dark- 

 reddish tinge, and the corpuscles are very much diminished. 



c. The blood of the placental vessels contains but little albumen 



1 The serum of the blood of the hepatic vein contains "but two-thirds as much 

 albumen as is found in the portal vein. The remaining one-third received from 

 the portal vein has probably been assimilated in the development of the blood- 

 cells which abound in the blood of the hepatic vein. 



2 On the Structure and Use of the Spleen. London, 1854. 



