24 E. A. Schäfer, 



this way tlie cells in question may be rej^arded as indirectly trans- 

 ferring tlie materials of nutrition from tlie alimentary canal into the 

 chyle and eventually into the blood. 



In thus contending for the agency of the amoeboid cells of the 

 mucous membrane of the intestine in the promotion of absorption 

 I woiüd by no means be understood to regard these as the sole agents 

 in the transference of the nutritive materials from the intestinal 

 Contents. In aU probability a large amoimt of these materials must 

 pass in a fluid condition through the tissues of the mucous membrane 

 and into the lacteals and bloodvessels. At the same time it cannot 

 be admitted that this passage is due to a simple physical process of 

 diffusion or flltration. For as Hoppe -Seyler') clearly points out it 

 is dependent upon the integrity of the epithelium cells, being thus 

 analogous to a secretory process, and having this also in common with 

 such a process that it takes place even with the fluid pressure against 

 it. And when the membrane is denuded of its epithelium, not only 

 is there not an increased rapidity of absorption, which should under 

 such circumstances occur if due to osmosis or flltration, but the flow 

 of fluid may even be in the opposite direction so that the intestinal 

 Contents become more watery. 



Many observations have been accumulating of late which tend 

 to show the importance of the part played by amoeboid cells 

 in the promotion of various absorption processes. Such observations, 

 since they prove that the transference of materials which is effected 

 by the lymph-cells in the intestinal mucous membrane is by no means 

 an isolated instance of their connection with the function of absorption, 

 may rightly be referred to in connection with the subject of this 

 article. Of these observations the most remarkable are those of 

 Metschnikoft' ^) , who describes the absorption of the tau of the ba- 

 trachian larva as being neither more nor less than the eating up of 

 the several tissues composing it by numerous leucocytes, which take 



Physiologische Chemie, II, S. 348. 



') Metschnikoff, Untersuchungen ü. d. mesoderiualeii Phagocyten einiger Wir- 

 belthiere. Biol. Centralbl., III, S. 560. 1883. 



