LYMPHATIC SYSTEM AND DUCTLESS GLANDS. 355 



the bile was long a puzzle. We now know that the chief use 

 of the liver is connected with the storage and formation of car- 

 bohydrate materials (see Chap. XXIX), and that, quite apart 

 from the use of bile in digestion or the elimination of part of 

 the bile as waste, the liver exerts an essential influence on the 

 whole normal nutritional processes of the Body. Again, in 

 the pancreas we have an organ which forms a very important 

 digestive secretion, and it might well be that this was its sole 

 use in the economy. But when the pancreas is carefully re- 

 moved from an animal great nutritional disturbances follow, 

 as shown, among other things, by diabetes, i.e., the presence 

 of sugar in the urine. Since the pancreatic secretion poured 

 into the intestine by the gland duct has much to do with the 

 digestion of starch and its conversion into sugar, it might be 

 supposed that mere digestive disturbances due to its absence 

 led to the diabetic and general changes. But this is not so. 

 If a piece of living pancreas be transplanted from one animal 

 to beneath the skin of another, and left until it has grown 

 there, the pancreas of the second animal may be removed 

 without causing diabetes. Moreover it is possible by inject- 

 ing melted paraffin into the pancreatic duct of an animal not 

 only to prevent the gland secretion from reaching the intes- 

 tine, but to cause atrophy of the true gland-cells. Yet 

 animals so treated do not become diabetic. It is then clear 

 that there is some material necessary to health and quite 

 distinct from pancreatic juice formed by pancreatic tissue and 

 taken up from it by the circulating liquids. Scattered through 

 the pancreas, and quite distinct from its proper gland tissue ? 

 are peculiar patches of cells very richly supplied with blood- 

 vessels. Probably these cells are concerned in the antidiabetic 

 function of the gland; but whether through special cells 

 or not, the organ has an important internal secretion to 

 blood and lymph, in addition to its external secretion to its 

 duct. This fact may have a very wide bearing: it may be 

 that all organs, or many organs, in addition to their more ob- 

 vious functions, do, as the result of the chemical processes 

 taking place in them, manufacture substances a supply of 

 which, to lymph or blood, is required for the life or health of 

 distant parts of the Body. The waste of one organ before its 

 final conversion into carbon dioxide, water, or urea, for elimi- 

 nation from the system, may be a necessary food of another. 

 It is, for example, quite possible that the kreatin formed in 



