64 NORMAL HISTOLOGY AND ORGANOGRAPHY. 



quickly formed. This is of the greatest importance 

 in preventing the spreading of an infection, as in 

 peritonitis. 



2. These cells act as phagocytes and feed upon 

 bacteria in case of an infection. According to one 

 view they can destroy living bacteria. A second 

 theory is that they act as scavengers and remove 

 only dead bacteria. 



Stomata and stigmata have been frequently de- 

 scribed as minute openings in these membranes to 

 facilitate the absorption of fluids. Stomata are 

 said to have guard cells to regulate the size of the 

 opening, and were supposed to be specially abundant 

 in the peritoneal lining of the diaphragm. The exist- 

 ence of stomata has lately been strenuously denied. 

 The rapid absorption of peritoneal fluid is a well- 

 established fact. If stomata are absent the ab- 

 sorption is purely one of osmosis or dialysis. It 

 should be remembered that drainage is along 

 lymphatic channels and therefore from the pelvis 

 toward the thorax. 



II. SUPPORTING TISSUE. 



The embryonic connective tissue is largely cellular, 

 but in the adult body the intercellular substance 

 greatly predominates and gives the characteristics 

 on which a classification is based. The cell elements 

 are but slightly modified from the embryonic type, 

 but the cell products or intercellular substance be- 

 come modified to form bone, cartilage, or connective- 

 tissue fibers. The difference here is relatively a dif- 



