ON CIRCULATION AND NUTRITION 175 



of vital integrative and cohesive force, has been ex- 

 hausted, in its long struggle against the powers of inorganic 

 activities, and the natural analytic disposition inherent in 

 metamorphic matter, it is conducted, certainly along paths 

 still actively alive, but in accordance with the disinte- 

 grative, "downhill," or adynamic, condition, of dying, or 

 dead, matter, and shed through the external surface exits 

 of the organism in question, into the outer world, in 

 quantity exactly according with that of the original raw 

 material ingested. 



This general process of nutritive circulation requires, 

 for the accomplishment of its purpose, the provision of a 

 " system " of circulatory facilities, or passages, amid the, 

 for the time being, existing matrix elements of the various 

 structures undergoing nutrition, along which the nutritive 

 pabulum can be conveyed, and from which it can be 

 selected, by anabolic attraction for incorporation with, and 

 integration by, the worn, and exhausted, tissues ; and we 

 claim that such a system is afforded by the endothelial 

 lining cells, with their connecting and continuing, fibrous 

 processes of the capillary network of the blood-vessels, 

 from which the materials for nutrition are extravasated, 

 and from which they circulate into the remotest interstitial 

 spaces of the tissue matrix, and proper structural elements, 

 throughout the organism. 



The process of extravasation, or exudation, or extraction, 

 here referred to, may be said to resemble what takes place 

 through the intestinal mucosa, and its overspreading, or 

 lining villi, the latter performing, in the process of ali- 

 mentary absorption, the same function as do the endothelial 

 cells lining the capillary blood vasculature, which pass their 

 absorbed plasma on to their process related cells ', for meta- 

 bolic, or nutritive, use, much in the same way as the villi 

 of the intestinal wall pass on their absorbed chyle, to the 

 lacteals, and related mesenteric glands. Moreover, both 

 these examples of distributive circulation illustrate the 

 adaptation, of the same principles of circulation, to meet 

 very different organic ends, and to accomplish very different 

 physiological purposes, in the economy of sympathetically 

 controlled nutrition. 



This view of the subject has already been referred to 



