590 ABSORBENTS OF THE TRUNK. 



vessels in their distribution through this organ. The cells 

 are filled with a bloody pulp, of a grumous character, in 

 which the microscope detects a number of small oval corpus- 

 cles, of a reddish color, and about the size of the red 

 globules of blood. The spleen contains also some small 

 bodies, called after Malpighi, which are described as being 

 about the third of a line in diameter, and consisting of con- 

 voluted blood-vessels and lymphatics, connected by elastic 

 tissue, and resembling minute lymphatic glands. They are 

 said to contain lymph of the color of milk. 



Blood-vessels. The splenic artery, the largest branch of 

 the cceliac, takes a tortuous course along the superior mar- 

 gin of the pancreas, and enters the hilum of the spleen by 

 five or six branches, which ramify minutely throughout 

 its substance. Injections have shown that the different 

 branches do not anastomose,, hence each branch is regarded 

 as having an independent function, and the spleen as con- 

 sisting really of several organs like the conglomerate glands. 

 The veins are numerous, having thin coats, and presenting 

 enlargements, which are compared to the corpus cavernosum 

 penis. These differ from the arteries by anastomosing 

 freely with each other, and unite to form the splenic vein, a 

 very large trunk, which is one of the principal roots of the 

 vena porta3. This vein, like the rest of the portal veins, is 

 without valves. 



The nerves come from the solar plexus and accompany 

 the artery. The lymphatics are superficial and deep, and 

 go to glands at the hilum. 



Function. The use of this organ is unknown, but, not- 

 withstanding this, there is no scarcity of speculations about 

 the matter. The most generally received theory is, that it 

 serves as a reservoir or diverticulum, when the abdominal 

 organs are threatened by undue congestion of the portal 



system. 



SECTION III. 



ORGANS OF ABSORPTION OF THE TRUNK. 



The organs of absorption naturally follow, in the physi- 

 ological arrangement, those of digestion; for while it is 



