326 ANATOMY IN A NUTSHELL. 



go directly into the liver. The nerves of the gall-bladder are from the coeliac 

 plexus. 



The hepatic duct is formed by the right and left bile ducts descending from 

 the liver. The biliary ducts are the cystic ducts which come from the neck of 

 the gall-bladder. It joins the hepatic forming the ductus communis chole- 

 dochus. These three are called the biliary ducts. The ductus communis chole- 

 dochus empties into the descending duodenum about three inches from the 

 pyloric end of the stomach. 



Pancreas means "all flesh, " (Plate CXLVIII). Insomeof the lower animals 

 it is known as the sweetbread. On account of closely resembling the parotid 

 glands it is called the abdominal salivary gland. It is situated in front of the 

 first and second lumbar vertebrse and behind the stomach. It has a head, a 

 neck, a body and a tail. It varies considerably in size, it is about six inches 

 long, from half an inch to one inch in thickness and weighs about three ounces. 

 The pancreatic duct, also called the duct of Wirsung, extends the whole length 

 of the pancreas and opens into the duodenum about three inches below the 

 pylorus often in common with the ductus communis choledochus. The head 

 or right extremity is surrounded by the curve of the duodenum, ductus communis 

 choledochus, and the pancreatico-duodenalis arteries. The tail or left extremity 

 lies above the left kidney and in contact with the lower end of the spleen. 



LESSON XCIII. 



The pancreas receives blood from the splenic artery through its pancreatic 

 branches, and from the superior mesenteric and hepatic by the inferior and 

 superior pancreatico-duodenalis arteries, which form a loop running round, below, 

 and to the right of its head. The blood is returned into the portal vein by 

 means of the splenic and superior mesenteric veins. The lymphatics terminate 

 in two glands which lie on the superior mesenteric veins. The nerve supply of 

 the pancreas is branches of the solar plexus which accompany the arteries en- 

 tering the gland. Sometimes a lobe of the head is detached and has a duct of 

 its own opening into the duodenum about an inch above the pancreatic duct. 

 This In be is called the lesser pancreas. 



Tin- portal vein (an appendage of the systemic system) is a single large 

 trunk which carries venous blood from viscera to the liver; there it splits up 

 into capillaries, which then unite to form the hepatic veins, which empty into 

 the inferior vena cava. 



The portal system (Plate CXXXVIII) consists of four large veins which 

 drain the viscera of digestion and unite to form the portal vein; the branches 

 correspond to those of the arteries, are always single, and have no valves. The 

 four veins are the splenic, gastric, and superior and inferior mesenteric. 



Si perior mesentkkic, ascends along the right side and in front of the 

 artery, passes in fronl of the transverse duodenum, and joins with the splenic 

 behind the upper bolder of the pancreas, forming the portal vein; it receives the 

 pancreatico-duodenalis and right gastroepiploic veins, and drains the csecum, 

 ascending and transverse colon, and small intestine. 



