DISSECTION OF THE DOG 



65 



Leaving the narrow neck of the gall-bladder (collum vesicae fellese) is the 

 cystic duct (ductus cysticus), to which are joined hepatic ducts (ductus hepatici) 

 from the central and left lateral lobes. The result of this union is the 

 production of the common bile-duct (ductus choledochus) which opens into 

 the duodenum. Mostly, the hepatic duct from the right lateral lobe joins the 

 common bile-duct independently. 



Arrangement of the peritoneum in connection Avith the liver. — Like other 

 abdommal organs, the liver is covered by visceral peritoneum, which gives 

 its surface a smooth, shining appearance. The visceral peritoneum becomes 

 continuous with the parietal peritoneum of the diaphragm by reflection along 

 the vena cava, which lies in a deep 

 groove (fossa venae cavae) on the dia- 

 phragmatic surface of the liver. Lateral 

 to the vena cava on each side is a double 

 fold of peritoneum connecting the right 

 and left lateral lobes to the diaphragm 

 — the right and left triangular ligaments — 

 and connected with the right ligament 

 is an offshoot binding the caudate 

 process to the right kidney. 



On the visceral surface of the liver 

 is a transverse depression, the porta 

 hepatis, from the margins of which the 

 peritoneum is reflected onto the lesser 

 curvature of the stomach in the form 

 of a thin membrane, the lesser omentum. 



Porta hepatis. — The porta of the liver is in the deepest part of a depression 

 circumscribed by the central lobe and the caudate and omental processes, and is 

 the place of entrance of the portal vein and the hepatic artery, and for exit 

 of the hepatic ducts and lymphatic vessels. 



Lohus lateralii 

 sinister 



Loins centralis 



- Vesica fellea 



Fig. 27. — Diagram of tho gall-bladder and its 

 associated ducts. The names of the lobes of the 

 liver are included in order to indicate the drainage- 

 area of each hepatic duct. 



Dissection. — Follow the oesophageal nerve trunks through the diaphragm 

 into the abdomen. The ventral nerve will be found to terminate over the 

 stomach, especially in the region of the lesser curvature and the cardia 

 whereas the dorsal nerve will lead to the coehac plexus and gangha. 



Trttncus cesophageus ventealis. — The formation of the ventral oeso- 

 phageal trunk has been seen to result from the union of the ventral branches 

 of the two vagus nerves. Following the oesophagus into the abdomen, the 

 nerve divides into many small branches which form a plexus chiefly disposed 

 over the cranial surface and cardia of the stomach. The larger filaments of 



