456 LABORATORY MANUAL OF HUMAN ANATOMY 



rior ossis pubis. Reflect this flap laterally and downward. Note 

 the fan-like attachment of the cord-like linea alba to the ossa 

 pubis (this is the adminiculum lineae albae). 



Internal Surface of Anterior Abdominal Wall. (Fig. 234.) 

 Note 



(a) A fibrous cord (urachus), passing from the umbilicus downward to 



the urinary bladder (vesica urinaria). 



(aa) Middle umbilical fold of peritoneum, over this (plica umbili- 

 calis media). 



(b) A second cord, passing from the umbilicus to the lateral margin of 



the obliterated umbilical artery. (Spalteholz, vol. ii., Fig. 

 511.) 



(ba) Lateral umbilical fold of peritoneum, over this (plica umbili- 

 calis lateralis). 



(c) Band extending from linea semicircularis [Douglasi] to a point oppo- 



site the middle of the inguinal ligament. This is the A. 

 epigastrica inferior and accompanying vein. 

 (ca) Epigastric fold (plica epigastrica). 



(d) The three foveae thus formed: 



(da) Medial supravesical fovea (fovea supravesicalis) . By which 



plicae is this fovea limited? 



(db) Medial inguinal fovea (fovea inguinalis medialis). 



(dc) Lateral inguinal fovea (fovea inguinalis lateralis). Note 



especially its relation to the plica epigastrica. The deepest 

 part of this fovea is a depression in the peritoneum indi- 

 cating the position of the abdominal inguinal ring (annulus 

 inguinalis abdominis) (0. T. internal abdominal ring), the 

 beginning of the inguinal canal. In what structure is this 

 annulus formed? 



What is Hesselbach's triangle? Note carefully its boun- 

 daries. 



Inguinal Canal (Canalis inguinalis). (Vide Fig. 233.) 



Dissect the peritoneum away carefully from the anterior wall 

 of the abdomen. Examine 



Posterior wall of inguinal canal. 



Note the following structures : 



(a) Thickened fold of fascia forming the lower and medial boundary 



of the annulus inguinalis abdominis (ligamentum interfoveolare) 

 (0. T. Hesselbach's ligament). 



(b) Thin layer of fascia transversalis. 



(c) Interfoveolar muscle (M. inter foveolaris) (0. T. Luschka's muscle). 



(d) Medialward the inguinal aponeurotic falx (falx aponeurotica in- 



guinalis) (0. T. conjoined tendon). What muscles enter into 

 the formation of it? Note carefully its insertion. Pay par- 

 ticular attention to its relation to the annulus inguinalis sub- 

 cutaneus. 



