ORGANS OF THE BODY. 511 



they merge, either as distinct vessels or interlobular lacunae, into a very 

 remarkable network of lymphatic passages, traversing the whole lobule in 

 every direction. Every blood capillary, namely, is ensheathed in a lymph 

 stream, whose external boundary is without doubt formed by the delicate 

 fibrous sustentacular membrane of the hepatic cell bands ; so that each 

 of the cells of such a band bounds, with a portion of its surface, the inter- 

 lobular lymph stream. We are indebted to MacGillairy for the discovery 

 of these perivascular lymphatic spaces ( 207). These facts we have 

 confirmed by personal observations, and Biesiadecky has recently succeeded 

 in demonstrating that the same arrangement of parts prevails in the 

 human liver. Incautious injection of the biliary capillaries frequently 

 results in rupture of the latter, and communication between them and the 

 lymphatic interlacements, giving rise to appearances which have led at 

 least several observers into the error of regarding the latter as biliary 

 networks. 



The nerves of the liver, springing for the most part from the plexus 

 cceliacus, and consisting of both Remains fibres and other dark, fine, or 

 broader filaments, spread themselves along the course of the bile-ducts, 

 along the hepatic arteries and its ramifications, as far as its interlobular 

 branches, along the portal and hepatic veins and serous covering of the 

 organ (Koelliker). The mode of their ultimate termination is still very 

 obscure. 



267. 



Turning now to the composition of the liver, older and rougher analyses 

 of its tissue (whose sp. gr. is stated by Krause and Fischer at 1'057) 

 give, beside about 70 per cent, of water for man, soluble albumen, 

 coagulated protein matters, glutinous substances, fats, extractives, and 

 about 1 per cent, of mineral constituents. 



In addition to these, a number of interesting mutation products have 

 been found in the liver. As far as we know at present, glycogen, 

 grape sugar, inosite (in the ox), lactic acid, uric acid, hypoxanthin, 

 xanthin, and urea have been met with here. Kreatin and kreatiniu, 

 on the other hand, have not been found, nor leucin and tyrosin, of which 

 the first is at the most only present in traces in the healthy liver ( 31 

 and 32). Cystin has also been found in the organ under morbid 

 conditions. 



]S T one of these matters are present in the bile, and must consequently 

 return into the circulation. 



The mineral constituents are, in the first place, phosphates of the 

 alkalies, which appear in large quantities, the salts of potassium prepon- 

 derating, while phosphate of calcium and magnesium, chlorides of the 

 alkalies and sulphates are present in but small amount. Iron, manganese, 

 and copper (p. 62), with traces of silicates, have also been found. 



Accurate observation has shown that the tissue of the liver, which is 

 of soft consistence during life, possesses also an alkaline reaction, while 

 in the dead animal it reacts acid. 



The glandular elements, or hepatic cells, are composed of richly albu- 

 minous protoplasm, containing frequently glycogen. This latter coin- 

 pound vanishes from the cells of starving animals. Glycogen, which is 

 neither found in the vegetable kingdom nor in the blood, must be 

 regarded as a product of cell life. Through the agency of a ferment also 

 existing in the cell, this substance is converted first into dextrin, as an 



