428 Chapter XIII 



certain antitoxic action of this organ, but, later, Charrin 1 convinced 

 himself that the bacterial secretions are only " moderately modified " 

 under these conditions, and that it is more especially the parts soluble 

 in alcohol which undergo modification in the liver. Now, the true 

 bacterial toxins, as is well known, are distinguished by their 

 insolubility in alcohol. Moreover in the numerous experiments made 

 by Roux and Vaillard and so many other observers on the tetanus 

 and diphtheria toxins there has never been any evidence of any kind 

 of antitoxic action of the liver. 



The digestive organs are furnished throughout with a defensive 

 [449] apparatus against micro-organisms ; this consists in an accumulation 

 of lymphoid tissue in the form of patches or groups of solitary 

 glands : the tonsils, Peyer's patches, and the solitary glands of 

 the intestine. These organs produce a large number of phagocytes 

 which are able to come into close contact with the micro-organisms. 

 Ribbert 2 and Bizzozero 3 have, independently or almost simultaneously, 

 described glandular masses in the coecum of the rabbit in which they 

 recognise the presence of many micro-organisms derived from the 

 intestinal content. They noted that the greater number of these 

 bacteria were within cells, and regarded this as an example of 

 phagocytic reaction. Manfredi 4 was able to confirm this interpretation 

 by the demonstration that the ingested micro-organisms were dead. 

 Later, Buffer 5 studied this question in my laboratory. He observed 

 intestinal phagocytosis in Peyer's patches in several species of animals, 

 and showed that the lymphoid tissue contained large macrophages 

 filled with bacteria and microphages in process of intracellular 

 digestion. Amongst these latter he recognised leucocytes, which in 

 turn contained micro-organisms. The accumulation of phagocytes 

 in the lymphoid organs of the digestive canal constitutes, so to speak, 

 the last act of a struggle which is spread over a very wide field. 



Some years ago Stohr demonstrated 6 that the wall of the intestine, 

 and especially the tonsils and other lymphoid organs, are traversed 

 by an enormous number of leucocytes which execute a kind of 

 migration towards the cavities containing micro-organisms. This con- 



" Les defenses naturelles de 1'organisme," Paris, 1898. 



2 Deutsche med. Wchnschr., Leipzig, 1885, S. 197. 



3 Centralb.f. d. med. Wissensch., Berlin, Jahrg. 1885, S. 801. 

 * Gior. internaz. d. sc. med., Napoli, 1886, p. 318. 



6 Quart. Journ. Micr. Sc., Lond., 1890, Vol. xxx, n.s., p. 481. 

 Virchow's Archiv, 1884, Bd. xcvn, S. 211. 



