128 American Quarterly Microscopical Journal. 



If in these cases we use terms to designate size, there can be 

 no reference to position, either absolute or relative, and hence 

 no comparison. It seems to me that all difficulty may be 

 avoided by choosing two fixed points by which to determine 

 the positions and names of the pancreatic ducts. The 

 pylorus has already served as one point, and the ductus com- 

 munis choledochus, which is single in all mammals so far as I 

 know, may serve as the other. 



As Wirsung was the discoverer of the pancreatic duct in 

 man, which opens into the intestine with the ductus choledochus, 

 that duct in all mammals which opens with or nearest it, may 

 be properly called the duct of Wirsung. This name is recog- 

 nized, at least as a synonym, by most anatomists (i, 3, 14, 20, 

 22, 23, 25, 27, etc.). And as Santorini was the first to accu- 

 rately describe and figure a second duct in man, opening sep- 

 arately into the intestine, the duct so opening independently 

 and the farther from the ductus choledochus, may be called, in 

 all mammals, the duct of Santorini, without regard to its size. 

 This name is also recognized by good authority (8, 750 and 

 18, 1137). 



To briefly recapitulate : Comparison, both in human and 

 comparative anatomy, would always be easy and intelligible if, 

 where two pancreatic ducts are known to exist, the one open- 

 ing with or next the ductus choledochus, were called the duct 

 of Wirsung, and the one opening independenly and farthest 

 from the ductus choledochus were called the duct of Santorini, 

 without regard to size. Where but one duct is known, it 

 should probably be called the duct of Wirsung.* 



The form, position, and relation of the cat's pancreas may 

 be well shown, as in Plate XII., Fig. I., by killing a fasting ani- 

 mal with chloroform, and securing it on its back with the legs 

 horizontal and at right angles to the trunk. After it has 

 stiffened, if the abdominal wall be removed, the great omentum 

 turned over upon the thorax, the liver over the right hypo- 

 chondrium, turning the concave side uppermost, and the 

 jejunum and ileum into the left hypogastrium, the pyloric re- 

 gion of the stomach with the pancreas and duodenum will appear 

 in situ. The pancreas (PI. XII., Fig. I., 4 and 5) consists of two 

 main divisions, one of which extends from the pylorus along 



*For a consideration of the necessity of uniformity in anatomical nomenclature, see Quain 

 (25, 1., 20), Pye Smith in the Journal oj Anatomy and Physiology (30, 15), and Wilder (36). 



