POINTS IN MINUTE STRUCTURE OF PANCREAS. J 85 



supply^ that they can be merely the remains of embryonic 

 tissue. 



Looking at the diverse functions of the pancreas may they 

 not take some share therein ? 



I have not yet had an opportunity of injecting the human 

 pancreas. 



Another peculiarity in the pancreas, which so far as I know 

 has not been recorded, occurs in the duct. 



After the intermediary part the duct becomes lined with 

 columnar cells, at first short, then longer, a fibrous connective- 

 tissue sheath is gradually formed round the duct. This becomes 

 thicker as the duct approaches the surface. 



At some distance from the surface the duct is very large and 

 of an oval shape. It is lined by a single layer of columnar 

 cells; these rest on a varying amount of fibrous connective 

 tissue. Between this lining epithelium and the fibrous con. 

 nective-tissue sheath, there is a complete circle of mucous 

 glands; they consist of distinct tubes lined by large cells 

 having a well-defined network. The different alveoli are 

 separated by fibrous trabeculfe continuous with the outer 

 sheath (see PI. XIV, fig. 3). 



The ducts having these mucous glands vary very much in size, 

 one section will often show two ducts one three times as large 

 as the other. The drawing was made from one of the largest. 



These mucous glands have a very large blood supply, there 

 being a dense plexus of capillaries between them and the lining 

 epithelium and also on the outside under the fibrous sheath. 



They are very well seen in the pancreas of the guinea- pig. 



In a pancreas of the cat I found a small accessory spleen, 

 which had grown round some of the alveoli and isolated them 

 from the rest of the organ ; a single minute duct from the 

 pancreas lined by columnar cells passed through it. 



In another part of the same pancreas there was a small mass 

 of splenic tissue surrounded by a fibrous capsule, and in its 

 substance were several branched tubes from the pancreas. 



The whole of this lay amongst the pancreatic alveoli ; the 

 first described was attached to the side of the pancreas. 



