FUNCTIONAL MECHANISM OP THE PANCREAS. 381 



digestive leucocytosis prevails, and, an accompanying destruc- 

 tion of these cells yielding more oxidizing bodies, the latter, 

 he thinks, are the source of conversion of protrypsin or tryp- 

 sinogen into trypsin, which thus becomes a function of the 

 blood. Thus, the spleen would have nothing to do with the 

 process, the hyperaemia and dilation of this organ during the 

 formation of trypsin being regarded merely as concomitant 

 phenomena. 



The only feature of interest to us in Popelski's last paper 

 is the fact that his experiments were performed in accordance 

 with the directions of Schiff. That he should be driven thereby 

 to ascribe all the phenomena witnessed to the action of 

 "oxidizing bodies" adds materially to the data contributed by 

 Schmiedeberg, Jaquet, Abelous and Biarnes, and Salkowski, 

 proving experimentally the existence of an oxidizing substance, 

 and is suggestive. Indeed, when, in addition to this, we realize 

 the strength of Heidenhain's position, the manner in which 

 it shook to its very foundation the equally strong position of 

 SchifFs views as developed by Herzen, by pointing to the in- 

 fluence of oxygen as another agency through which trypsin 

 could be developed from trypsinogen, "trypsin being oxidized 

 trypsinogen," the following query suggests itself: Are we not 

 dealing with two processes working in sequence, a part of the 

 trypsinogen secreted in the splenic vein being converted by 

 the splenic secretion for use in the portal vein, and the rest 

 being converted, when the arteries are reached, by the oxidiz- 

 ing substance? 



To determine whether such a deduction is at all warranted 

 or whether it is subject to modifications through which the 

 various views submitted and our own can be conciliated, we 

 find it necessary to closely analyze the manner in which the 

 pancreas and the spleen are functionally governed. 



THE FUNCTIONAL MECHANISM OF THE PANCKEAS. The 

 pancreas will first receive our attention. Eef erring to this or- 

 gan, Howell says: "Until recently little direct evidence had 

 been obtained of the existence of secretory nerves. Stimulation 

 of the medulla was known to increase the flow of pancreatic 

 juice and to alter its composition as regards the organic constit- 

 uents, but direct stimulation of the vagus and the sympathetic 



