Ik iiiiericaii (liiniiDrlf licroscopical Joiinia 



Go forth, under the open sky, and list 

 To Nature's teachings." — Bryant. 



Vol I. New York, April, 1879. No. 3. 



THE AMPULLA OF VATER AND THE PANCREATIC 

 DUCTS IN THE DOMESTIC CAT {Felis domestica). 



BY SIMON H. GAGE, B. S. 



{Concluded^ 

 Microscopic Anatomy, 



The ducts of the pancreas are quite variable in size, but the 

 average for the duct of Wirsung is about 2>4 mm. and i mm. 

 for the duct of Santorini. The inner surface of the duct of 

 Wirsung is usually thrown into longitudinal folds. It is com- 

 posed of three tolerably distinct layers (PI. XIII., Fig. 3, a, b, c). 

 The inner layer of epithelium is composed of but a single 

 layer of broad low cells with a very large clear nucleus, and a 

 granular nucleolus. Many of the cells are divided at the base 

 (PI. XIII., Fig. 6, d), and alternating cells may have their thicker 

 extremities turned in opposite directions. There is no sign of 

 a striated margin as in PI. XIII., Fig. 5. 



The middle coat is very complex, but its main tissue is the 

 elastic. The fibers run both longitudinally and circularly. 

 The longitudinal fibers are quite coarse, while the circular ones 

 are very fine, and by their anastomosing make a complete net- 

 work. The middle coat is especially dense next the epithelium, 

 and contains many roundish nuclei, which take a deep color in 

 staining. The vascular supply of the pancreatic duct is very 

 great, and so thickly are the vessels placed that the middle coat 

 seems to be half composed of them (PI. XIII., Fig. 4). 



Finally, the outer layer is made up of areolar tissue which 

 becomes very loose and indefinite toward the outside, but to- 

 ward the middle layer it is quite dense, and receives many 



