THE SPLEEN. 



335 



proper duct, still there are added to the lymph during its passa 

 through the glands the lymphocytes, which are a product of the 

 gland, and it is now held that in a similar manner while the blood 

 is passing through the ductless glands their product is added to it 

 This product is regarded as an internal secretion. 



THE SPLEEN, 



The spleen is the largest of the ductless glands, and its func- 

 tion is, doubtless, the most important. Its location is in the left 



'** 



%,v^ 



3fe 



-'- - '^*?^?'* 



''iM^;^: 



';/ '*"" 



': V, 



V'l-.-.vS x ;-." /~/- '.'-^ '/. -S ( y " 

 ' $vl?*:Mi fe^>3i?V 



*l3 



Blood-vessel. 

 Trabecula. 



-Spleen pulp. 



ft Artery. 



|^- Malpighian cor- 

 fe. puscle with 

 m germ center. 



^'' 



"*^ : S^ftl*p 



FIG. 180. Part of a section through the human spleen : X 75 (sublimate fixation). 

 At a is an oblong Malpighian body with a blood-vessel (Bohm and Davidoff). 



hypochondrium between the stomach and diaphragm. Instances 

 are on record in which the organ was absent, while sometimes it 

 is so divided as to present the appearance of a considerable number 

 of small spleens. 



Weight. The weight of the spleen varies at different periods 

 of life, being at birth to the entire body as 1 is to 350 ; in adult 

 life, as 1 to 320 and 400 ; and in old age, as 1 to 700, while in 



