XXII] INTESTINE 177 



proper glands of Lieberkiihn. The raucous membrane is however 

 thrown up into considerable folds. In the osmic acid specimens, 

 the cells will probably be so full of deeply stained fat globules 

 that little structure can be seen in them except the hyaline free 

 border; in the submucous connective tissue few or no fat 

 globules are seen. 



In the alcohol specimens the cell substance will be seen as a 

 distinct sponge-work or network, the fat globules having been 

 dissolved. 



DEMONSTEATIONS. 



1. Vertical longitudinal section through the pylorus 

 and beginning of the duodenum, of cat or dog. Note: 

 the pyloric glands become shorter near the pylorus ; 

 at the beginning of the duodenum are Brunner's glands, 

 forming a layer external to the muscularis mucosae. In 

 places a duct may be seen running down into the sub- 

 mucous tissue, there it divides and subdivides, the end- 

 tubes enlarging slightly, and forming alveoli in which 

 as a rule the lumina are obvious. 



2. Vertical section of small intestine through a 

 Peyer's patch with blood vessels injected. Note the 

 collection of lymph follicles and compare with the 

 description given in 1, a. The capillaries in the 

 main radiate from the periphery to the centre of each 

 follicle. 



3. Section of Peyer's patch with the lymphatic 

 system injected. Note that the injected material 

 envelops to a greater or less extent each follicle; it 

 occupies the lymph sinus, and does not penetrate 

 into the interior of the follicle. 



L- 12 



