ABDOMEN AND PELVIS 



485 



and examine it with a pocket lens. About twelve villi are found 

 to the square millimetre (Sappey). Their total number is about 

 ten millions. Where are they most numerous? 



(c) Intestinal glands (Gl. intestinales [Lieberkuehni]) (0. T. crypts of 



Lieberkuehn). Look for their orifices with a lens. 



(d) Solitary lymph-nodules (noduli lymphatici solitarii). They are en- 



larged in many of the acute infectious diseases so as to be easily 

 visible. 



(e) Aggregated lymph-nodules of Peyer, or Peyer' s patches (noduli lym- 



phatici aggregati [Peyeri]). These should be studied carefully 

 and a correct idea of normal appearance be gained. They are the 

 seat of pathological changes in typhoid fever and often also in 

 tuberculosis. Notice that they are situated opposite the mesenteric 

 attachment. They are most easily found if the bowel is held to the 

 light. They number from thirty-five to forty (Sappey; fifteen 

 to fifty, Frey). What is their general form 1 ? Measure an elliptical 

 patch and note in drawing-book the measurements. What is the 

 general appearance of a patch? How is its long axis directed? 

 (Vide Fig. 255.) 



FIG. 255. 



Noduli lymphatici aggregati ( Peyeri) Noduli lymphatici solitarii 



Noduli lymphatici aggregati [Peyeri], " Peyer' s patch " of the intestinum ileum. Natural size. 

 (After Toldt, Anat. Atlas, Wicn, 1900, 2 Aufl., p. 426, Fig. 701.) 



Tabulate in your note-book the differences you have observed 

 between the intestinum jejunum and the intestinum ileum. 

 What are chyme (chymus), chyle (chylus), and intestinal juice 



(succus entericus) 1 



Large or Thick Intestine (Intestinum crassum). (Vide Fig. 256 and 

 Spalteholz, pp. 522-524.) 



Make use of models and determine accurately the course of 

 the intestinum crassum. Study its different parts : 



(a) Blind intestine (intestinum caecum). What are the foetal, infantile, 



