326 



THE DUCTLESS GLANDS. 



[CH. XXIII. 



causes: (i) a relaxation of the muscular tissue which forms so 

 large a part of its framework ; (2) a dilatation of the vessels. 

 Both these phenomena are under control of the nervous system. 



Fig. 299. Roy's Oncometer for spleen ; A, open ; B, closed. 



It has been found by experiment that when the splenic nerves are 

 cut the spleen enlarges, and that contraction can be brought 

 about by stimulation of the peripheral ends of the divided nerves. 

 If the splenic nerves are not cut, contraction is produced by 



