1064 THE ORGANS OF DIGESTION. 



The gall-bladder is pear-shaped. It is directed, with its broader rounded end 

 downward and forward and to the right to the anterior margin of the liver, and with 

 its sharper end backward and upward toward the transverse fissure. It is 7 to 8 

 cm. long (three or four inches) and near the fundus 2.53 cm. broad (over an inch), 

 and will contain 30-50 cc. of bile (1-1J ounces). There are to be distinguished 

 &fundus< a body, and a neck. It is fastened to the liver by connective tissue and 

 vessels, and lies in the fossa vesicalis. The fundus extends beyond the anterior 

 margin of the liver in the region of the incisura vesicalis. But in a normal posi- 

 tion of the liver, the gall-bladder may be placed more or less behind this edge. 

 The position of the fundus is usually at the lower edge of the ninth costal carti- 

 lage on the outer edge of the right Rectus muscle. Here it rests directly on the 

 abdominal wall. When it extends beyond the liver it can be percussed. Its 

 function is more than a storehouse. It forms some of the constituents of the bile. 

 Exceptionally it lies more to the right or more to the left. 



The fundus rests usually on the transverse colon and farther back on the upper 

 end of the descending duodenum, or on the pylorus. This part is usually stained 

 by biliary coloring matter after death. The neck of the bladder usually extends 

 in the posterior arid upper part of the vesical fossa close to the transverse fissure. 

 It is continued in a spiral curve into the cystic duct. This curving corresponds on 

 the inner surface to a constant more or less well developed screw-like valve which 

 runs through the Avhole cystic duct, Valvula Heisteri. 



The upper surface is attached to the liver by areolar tissue and vessels. Its 

 under surface and fundus are covered by peritoneum reflected from the liver sur- 

 face. Sometimes the peritoneum completely surrounds the bladder, suspending it 

 by a mesentery from the under surface of the liver. The gall-bladder is not present 

 in all vertebrates. It is lacking in some mammals and birds, but is present in all 

 reptiles, and nearly all fishes. The ass, horse, elephant, and rhinoceros do not 

 have it. 



Relations of the Gall-bladder. 



Superiorly : 



Liver (Fossa vesicalis). 

 Anteriorly : 



Abdominal wall ; and ninth costal cartilage. 

 Inferiorly : 



Hepatic flexure of colon ; 



Beginning of transverse colon ; 



Duodenum, first and second parts ; 



Pyloric end of stomach. 



Vessels and Nerves. It is supplied by the cystic artery from the right branch 

 of the hepatic. Two cystic veins usually empty into right branch of the vena 

 portse. Twelve or fifteen from the fundus go directly into liver. 



The nerves are from the coeliac plexus. 



The lymphatics are numerous and empty into a gland on the neck of the 

 bladder. 



The cystic duct, the smallest of the three, running from the neck of the gall- 

 bladder is 37 cm. long (one to three inches) and 2.3 mm. wide. Its course is 

 toward the left, at first a little curved and then straight. It joins the hepatic duct 

 at an acute angle to form the common duct. This is contained in the edge of the 

 lesser omentum. 



The ductus choledochus (xokq, bile, doxo^, which receives) is the largest of the 

 three, and is the common excretory duct of both liver and gall-bladder and con- 

 veys the bile to the duodenum. The length is various depending upon the point 

 of meeting of its two tributaries: 78 cm. (Sappey) ; 24.5 (Luschka) ; 67 cm., 

 or about three inches (Joessel), and 5.6 mm. to 7.5 mm. wide (one-fourth inch). It 



