212 



HISTOLOGY. 



A 



A, Diagram of the blood vessels of the small intestine; the arteries appear as coarse black lines, the 

 capillaries as fine ones, and the veins are shaded (after Mall). B, Diagram of the lymphatic vessels 

 (after Mall). C, Diagram of the nerves, based upon Golgi preparations (after Cajal). The layers of 

 the intestine are m., mucosa; m. m., muscularis mucosae; s - m - submucosa; c. m., circular muscle; 

 i. c., intermuscular connective tissue; 1. m., longitudinal muscle; s., serosa. c. 1., central lymphatic; 

 n., nodule; s. pi., submucous plexus; m. pi., myenteric plexus. 



at the periphery (Fig. 239), or on one side of the villus with a vein on the 

 other. The network of blood vessels in the villi is very abundant as shown 



Vein. 



Tunica propria. ../!_ 





Muscularis mucosae. Submucosa. 



FIG. 240. VERTICAL SECTION OF THE Mucous MEMBRANE OP THE HUMAN JEJUNUM. X 50. 

 The blood vessels are injected with Berlin blue The vein of the first villus on the left is cut transversely. 



in Fig. 240. The veins branch freely in the submucosa and pass out of the 

 intestine beside the arteries. The muscularis mucosae has been described 



