BLOOD. 2Ui 



organs of the auimal economy. Even in the embryo, the de- 

 velopment of its cells is wonderfully abundant, as has been 

 shown by Reichert. In the adult the activity of the liver 

 is exhibited by the increased secretion of the bile dui-ing di- 

 gestion. The activity of an organ is represented by the in- 

 tegral of the activity of its cells ; and the increased activity of 

 the cells is intimately connected with the facility of evolution 

 and revolution. If, then, in consequence of the activity of 

 the liver as a secreting organ, a large number of cells are con- 

 sumed, it follows that a proportionably large number must be 

 reproduced; and we can thus explain the apparently incon- 

 sistent phenomena of the blood of the hepatic vein containing 

 less fibrin than that of the vena porta3, by the supposition that, 

 although a large quantity of blood- corpuscles is consumed by 

 the liver, the fibrin of the plasma supplies the materials for the 

 formation of c}i;oblasts for new cells. 



All the other diiferences that are observable between the 

 composition of the blood of the hepatic vein and of the vena 

 port?e may be accounted for by paying a little attention to the 

 nature of the bile. 



The bile contains a smaller proportion of solid constituents 

 than the blood ; hence it is obvious that the blood, previously 

 to the separation of the bile [i. e. the blood of the vena porta3) 

 must contain a smaller proportion of sobd constituents than after 

 this change has been effected (i. e. the blood of the hepatic 

 vein.) 



The blood of the vena portse contains more colouring matter, 

 both hsematin and hsemaphsein, than that of the hepatic vein. 

 It is impossible to decide with certainty upon the manner in 

 which these colouring substances are consumed in the liver, as 

 we are still deficient in correct ultimate analyses of biliphsein 

 and hsemaphsein; we may, however, safely conclude that the 

 biliphsein is produced by the metamorphosis of the colom-ing 

 matter of the blood. 



Propei'ties of the blood of the renal veins ; — its comparison 

 with the blood of the aorta. 



The blood of the renal veins was drawn from a horse simul- 

 taneously with the aortic blood; it was found, however, upon 

 opening the body of the horse, bled to death, that the renal 



