324 



THE DUCTLESS GLANDS. 



[CH. xxiii. 



just referred to (see fig. 298). Blood capillaries traverse the 

 Malpigluan corpuscles and form a plexus in their interior. The 

 structure of a Malpighian corpuscle of the spleen is practically 

 identical with that of a lymphoid nodule. 



Functions. These are the following : 



(i.) The spleen, like the lymphatic glands, is engaged in the 

 formation of colourless blood-corpuscles. For it is quite certain, that 





Fig. 298. Section of spleen of cat. a, a', Malpighian corpuscle ; in the case of ', the con- 

 nection with a small artery, I, is seen ; b, b', small arteries ; c, section of trabeculee. 



the blood of the splenic vein contains an unusually large proportion 

 of white corpuscles ; and in the disease termed leucocythoemia, in 

 which the white corpuscles of the blood are remarkably increased 

 in number, there is found a hypertrophied condition of the spleen, 

 especially of the Malpighian corpuscles. The white corpuscles 

 formed in the spleen also doubtless partly leave that organ by 

 lymphatic vessels. 



By stimulating the spleen to contract in a case of splenic 

 leucocythsemia by means of an electric current applied over it 



