CHEMICAL PHYSIOLOGY. 45 



tumours or lipomata. Fat in tissue may originate in 

 several ways ; it may have been eaten with the food, 

 and after absorption have only been carried to the cells ; 

 orit may be formed from sugar, dextrine, and glykogen ; 

 or lastly, it may owe its existence to the decomposition 

 of albumen. Thus the cholic acid of bile might easily 

 yield any of the fatty acids, and sugar the glycerine. 

 But the proofs of any of these processes have not yet 

 been furnished. 



Cartilage contains peculiar cells and chondrinogen, cartilage. 

 or a substance which by boiling becomes chondrine. 

 This matter gelatinises like gelatine, but is not soluble 

 in acetic acid, on the contrary is precipitated by it. 

 Boiled with hydrochloric acid, chondrine yields sugar. 



The chemical composition of the cornea is similar to C omea. 

 that of cartilage, particularly the hyaline variety. 



The fluids of the eye, particularly the vitreous body, 

 contain much potassium chloride and little organic 

 matter. 



The cartilages are subject to a degeneration which ossification. 

 terminates in ossification. 



The cartilage surfaces of joints are lubricated by a synovia. 

 fluid which is termed synovia. It contains about 94 

 per cent, of water, 3 '5 of albumen, 0*5 of mucine, and 

 more than 1 per cent, of ash. Its origin is not yet 

 satisfactorily explained. During diseased conditions 

 of joints much synovia can be detected ; the collection 

 of excess of synovia in a joint constitutes hydrarthron. Hydrarthro 



A matter similar to chondrinogen is hyaline, of which Hyaline. 

 the cysts of old echinococci are composed. Boiled 

 with dilute sulphuric acid it yields, like the chitine of 



