214 



HISTOLOGY 



They are described as megakaryocytes, and are like those in bone marrow. 

 The formation of granular leucocytes, which has been asserted, presum- 

 ably does not occur. 



The splenic nodules are quite like the secondary nodules of lymph 

 glands. They consist of a reticular tissue framework continuous with 

 that of the pulp, but having coarser meshes. Fine elastic fibers are as- 

 sociated with it. It contains lymphocytes, and near the central arteries 



**._ Surface blackened 

 by precipitate of 

 silver. 



Nerve branches 



tor the arterial 



wall. 



~ -- Nerves of the pulp. 



\ 



Small nerve . . 

 bundle. 



Branches for the , , 

 arterial wall..'-' ' 

 Fie. 202. GOLGI PREPARATION OF THE!SPLEEN OF A MOUSE. X 85. 

 The boundary between the splenic pulp and the lymphoid tissue is indicated by a dotted line. 

 The nerves are chiefly in the wall of an artery. 



germinal centers are sometimes distinct. The nodules have been regarded 

 as varying in shape from time to time, being but transient accumulations 

 of lymphocytes. 



The capsule of the spleen is divided into two layers. The outer is 

 the tunica serosa and the inner, the tunica albuginea. The serosa con- 

 sists of the peritoneal mesothelium, which covers the spleen except at 

 the hilus, and of the underlying connective tissue. The albuginea is a 

 dense layer of connective tissue, containing elastic networks and smooth 

 muscle fibers. Similar tissue is found in the trabeculae. The muscle 



