DEVELOPMENT OF LIVER AND PANCREAS 



233 



Choronshitzky it is probable his lateral cylindrical extensions 

 are the early hepatic ducts. In Amblystoma these lateral ex- 

 tensions form only the lateral rami of the hepatic ducts. The 

 medial rami are shown in the model of an embryo about 7 mm. 



Fig. 18 Graphic reconstruction (lateral view) of the biliary apparatus of 

 an Amblystoma embryo 13 mm. long. X 100. D., duodenum; D choL, ductus 

 choledochus; D.h.d., right hepatic duct; D.cy., cystic duct; G.b., gall bladder; 

 R.l.d., right lateral ramus; R.l.s., left lateral ramus; R.m.d., right medial ramus; 

 R.m.s., left medial ramus; P.D., pancreatic duct. 



Fig. 19 Graphic reconstruction (lateral view) of the biliary apparatus of 

 an embryo approximately 13.5 mm. long. X 100. For abbreviations see figure 

 18. 



long (fig. 36). On the right side in this model there is a lateral 

 extension of the hepatic lumen. A longitudinal ridge in the 

 floor of this side shows a beginning constriction into lateral and 

 medial rami. The medial ramus is more dorsal in position and 

 appears as a swelling on the outer surface. On the left side there 



