474 LABORATORY MANUAL OF HUMAN "ANATOMY 



neum! Demonstrate three methods by which the pancreas can 

 be exposed anteriorly. 



How can the kidney be reached from the anterior abdominal 

 wall ? What structures may be taken as guides to it ? Note espe- 

 cially the relation of the kidneys to the ascending colon and de- 

 scending colon, duodenum, and liver. 



Locate accurately the position of the appendix. Do the longi- 

 tudinal bands passing out on to the caecum ever serve as a guide ! 

 What are these longitudinal bands called ? The tip of the appen- 

 dix is found sometimes directly beneath the liver. How do you 

 explain this 1 



After having gained an accurate knowledge of these different 

 folds, fossae, etc., the student should trace the peritoneum longi- 

 tudinally and transversely, demonstrating that the layers form- 

 ing the greater and lesser sacs are continuous. Transverse 

 tracings should be made (a) at the level of the foramen epiploi- 

 cum [Winslowi] and (b) at a level below the transverse colon. 

 (See Figs. 245 and 246.) Use transverse sections of a body 

 hardened in formalin in this study. 1 



Superior Mesenteric Artery (A. mesenterica superior) and its 

 Branches. (Fig. 248.) 



Turn the great omentum and transverse colon upward upon 

 the thorax. Remove the anterior leaf of the mesentery by blunt 

 dissection from the flexura duodenojejunalis downward as far 

 as the terminal portion of the ileum; remove the peritoneum 

 passing from the posterior abdominal wall upon the intestinum 

 caecum and colon ascendens and also the inferior layer of the 

 mesocolon transversum. 



Study the following branches of the superior mesenteric 

 artery. (Vide Fig. 248, and Spalteholz, Fig. 466.) 



(a) Inferior pancreaticoduodenal artery (A. pancreaticoduodenalis in- 



ferior). 



(b) Intestinal arteries (Aa. intestinales) . 



(ba) Jejunal arteries (Aa. jejunales). 



(bb) Heal arteries (Aa. ileae) (0. T. rami intestini tennis). 



(c) Ileocolie artery (A. ileocolica). 



(ca) Appendicular artery (A. appendicularis) . 



(d) Right colic artery (A. colica dextra). 



(e) Middle colic artery (A. colica media). 



1 See foot-note, p. 403. For a method of making cross-sections consult Pro- 

 fessor C. M. Jackson's paper in the Jour. Am. Med. Assoc. 



