PANCREAS OF THE PIG 213 



the figures. The tail of the pancreas is suppUed with blood by 

 one or more arteries from tlie splenic branch of the coeliac axis; 

 the head is supplied by the superior pancreatico-duodenal branch 

 of the coeliac axis ; and the descending process is partly fed by the 

 inferior pancreatico-duodenal from the superior mesenteric trunk. 

 There is normally one duct, since in the pig the duct of the dorsal 

 pancreas alone persists (Stoss '91; Wlassow '95; Thyng '08) 



Fiji- 1 Pancreas and duodenum of a 120 mm. pig foetus, dorsal aspect. Arte- 

 rial and capillary blood-vessels injected with ink from aorta. D, duodenum; H, 

 head of pancreas; T, tail of pancreas, showing lobulation; UB, 'upper bridge;' 

 LB, 'lower bridge.' X 4^. 



As shown in the figures (2, 13) it sends branches to all parts of 

 the gland. It is clearly seen from the diagram (fig. 2, A) that 

 since the duct and blood-vessels enter the organ at different 

 points, there is no constant relation between the branches of the 

 duct and the arteries. In one part of the pancreas the two sys- 

 tems run parallel, in another they may course in opposite direc- 

 tions (see below, p. 233). 



The secretory tissue is not homogeneous, but is di\'ided off 

 into small rounded masses, which are clearly seen with the naked 

 eye, in the tail of the pancreas, standing apart like a branch of 

 grapes in the jelly-like mesenchymal tissue (fig. 1). Toward the 

 head they are condensed and crowded togethei', but may be 



