SECRETION. 



411 



cythasmia. The spleen, from its power to dilate, serves as a reser- 

 voir of blood for the portal system, especially for the blood-vessels 

 of the stomach. Many of the purin bodies are found in the spleen, 

 as xanthin, hypoxanthin, and uric acid. 



Influence of the Nervous System Upon the Spleen. The nerves 

 that supply the spleen have their center in the medulla oblongata. 



Fig. 148. Effect of Extract of Spleen on Intestinal Peristalsis. 



Section of these nerves is followed by an increase in the size of the 

 organ. 



It has been shown by the oncometer that the spleen undergoes 

 rhythmical contractions and dilatations by virtue of the regular con- 

 traction and relaxation of the muscular fibers found in its capsule 



U. 3 



Fig. 149. Adrenal Capsules of a Rabbit. (MOEAT and DOYON.) 



C.a.d, C.s.g, Capsules. R.d, R.g, Kidneys. U.g, Ureters. A, Aorta. 

 V.c, Vena cava. 



and trabeculae. Jones, of Baltimore, has shown that the spleen con- 

 tains adenase, a ferment which converts adenin into hypoxanthin. 



I have demonstrated experimentally that extract made from the 

 spleen when injected into an animal will excite active peristaltic 

 movements. 



