416 



SCIENCE PROGRESS. 



The last three experiments in the table are those which 

 Heidenhain performed, and it will be seen how fallacious it 

 is to argue that a fall in arterial blood pressure necessarily 

 implies a fall of pressure in all the capillary areas of the 

 body ; and Starling devotes his third paper to pressing this 

 point home in special reference to Heidenhain's work, with 

 the result that he regards intra-capillary pressure as the 

 chief factor in lymph production. To take the three 

 experiments just referred to : In obstruction of the aorta 

 the lymph flow still goes on, though in diminished quantity ; 

 this is because the capillary pressure in the liver is either 

 unaffected, or undergoes a slight rise, the lymph which con- 

 tinues to flow coming from the liver ; in obstruction of the 

 inferior vena cava, the large increase of lymph is due to the 

 very large increase of capillary pressure in the liver, whereas 

 in obstruction of the portal vein the increase is due to rise 

 of capillary pressure in the intestines and other parts of the 

 portal area. 



We may here in passing allude to Hamburger's 1 work 



x Zeitsch.f. Biol., xxx., p. 143 (1893). 



