THYMUS AND SPLEEN. 369 



besides arginase, guanase, adenase, and proteolytic enzyme we must 

 especially mention the enzyme studied by JONES, 1 which acts like a nu- 

 clease, splitting off phosphoric acid and purine bases, from the nucleo- 

 proteins. This enzyme, contrary to trypsin, acts best in acid liquids, and 

 is readily destroyed by alkalies at body temperature. The quantitative 

 composition of the lymphocytes from the thymus of a calf is, according to 

 LILIENFELD'S analysis, as follows. The results are given in 1000 parts 

 of the dried substance: 



Proteids 17.7 



Leuconuclein 687 . 9 



Histone 86.7 



Lecithin 75. 1 



Fat 40.2 



Cholesterin 44.0 



Glycogen 8.0 



The dried substance of the leucocytes amounted to an average of 

 114.9 p. m. Potassium and phosphoric acid are prominent mineral 

 constituents. LILIENFELD found KH^PCU among the bodies soluble in 

 alcohol. 



Attention must be called to the analyses of BANG, 2 which show that 

 the thymus contains about the same quantity of nucleoprotein, but about 

 five times as much histone nucleate as the lymphatic glands calculated 

 in both cases upon the same amount of dry substance. OIDTMAN 3 found 

 807.06 p. m. water, 192.74 p. m. organic and 0.2 p. m. inorganic sub- 

 stances in the gland of a child two weeks old. 



In regard to the functions of the thymus it seems to be the general 

 view that this gland takes part in the recruiting of the blood lympho- 

 cytes and correspondingly belong to the lymphoid organs. On the other 

 hand also certain other observations indicate that it may belong to the 

 endocrinic organs. It is generally admitted that the extirpation of the 

 thymus leads to a reduction and change in the formation of bone. A 

 certain relation also exists with the organs of generation and perhaps 

 a reciprocal action also exists between it and other organs with internal 

 secretion. 



The Spleen. The pulp of the spleen cannot be freed from blood. 

 The mass which is separated from the spleen capsule and the structural 

 tissue by pressure, and which ordinarily serves as material for chemical 

 investigations is, therefore a mixture of blood and spleen constituents. 

 For this reason the proteins of the spleen are little known. The nucleo- 

 protein isolated by LEVENE and MANDEL 4 is to be considered as a true 



1 Zeitschr. f. physiol. Chem., 41. 

 2 1. c., Arch. f. Math., etc. 



3 Cited from v. Gorup-Besanez, Lehrb. d. physiol. Chem., 4. Aufl., p. 732. 



4 Bioch. Zeitschr., 5. 



