132 PHYSIOLOGICAL CHEMISTRY. 



we must specially recall the abundant re-formation of leucocytes in 

 leucaemia and the appearance of amyloid substance (see page 39). 



The physiological functions of the spleen are little known. 

 Some consider the spleen as a melting organ o the red blood-cor- 

 puscles (KOLLIKER, ECKER), and the occurrence of the above-men- 

 tioned iron deposit seems to confirm this view. Some (GERLACH, 

 FUNKE, and others) regard the spleen as a blood-forming organ. 

 Other investigators consider that steps in the modelling of the red 

 blood-corpuscles occur in the spleen or that young red blood-cor- 

 puscles occur in the blood of the splenic vein. 



The spleen has also been claimed to play an important part in 

 digestion. The organ is known to enlarge after a meal, and this 

 enlargement is thought by SCHIFF and HERZEK to be dependent 

 upon the filling of the pancreas with enzymes. According to the 

 above-mentioned investigators, after the extirpation of the spleen 

 the pancreas does not produce any enzyme, which digests albumin, 

 but HEIDENHEIM and EWALD have not been able to confirm this 

 fact. According to later investigations of HERZEN, an enzyme 

 which digests albumin is produced in the spleen during its enlarge- 

 ment. 



An increase in the quantity of uric acid eliminated occurs in leu- 

 caemia (RANKE, SALKOWSKI, FLEISCHER and PENZOLDT, and STADT- 

 HAGEN)", while the reverse ol this takes place under the influence 

 of quinine, which produces an enlargement of the spleen. We have 

 here a rather positive proof that there is a close relationship between 

 the spleen and the formation, of uric acid. If we assume that the 

 xanthin bodies are steps to the formation of uric acid, then the in - 

 crease in the uric acid in leucaemia may perhaps depend on the in- 

 creased amount of xanthin bodies (hypoxanthin) in the spleen in 

 this disease.* 



The spleen has the same property as the liver of retaining foreign 

 bodies, metals and metalloids. 



The Thymus has been little studied. Besides proteids and sub- 

 stances belonging to the connective group, we find small quantities 



* HOKBACZEWSKI has lately found in the spleen the first steps in the for- 

 mation of uric acid, and he has also shown that when the spleen and blood of a 

 calf are allowed to act on each other at the temperature of the blood and in the 

 presence of air, large quantities of uric acid are formed. 



