506 



extent, corresponding to the variable development of the processus 

 papillaris. In addition to this individual variation, I find also a vari- 

 ation according to the age of the foetus. From the figures and de- 

 scriptions of SwAEN (12) and Broman (3) it is evident that in the 

 earlier stages (first six weeks), the processus papillaris of the liver is 

 poorly developed, and does not come into contact with the pancreas. 

 In the latter part of the second month, however, I find the processus 

 papillaris extending downward behind the lesser omentum, and in 

 contact with the upper aspect of the body of the pancreas near its 

 inner end (corresponding to the neck) behind the lesser curvature of 

 the stomach. At first, this area papillaris of the pancreas faces 

 almost directly upward, so that the pancreas here presents four sur- 

 faces, superior, inferior, anterior and posterior. In older foetuses the 

 processus papillaris is found extending downward more and more (the 

 extent varying in individual specimens) over the anterior surface of 

 the body and neck of the pancreas, finally almost or quite reachiüg 

 the lower border. At its maximum development, the area papillaris 

 covers most of the anterior surface of the inner half of the body of 

 the pancreas extending inward across the neck and reaching the upper 

 part of the anterior surface of the head (Figs. 4, 6). Aside from the 

 numerous individual variations, the processus papillaris appears to 

 reach its maximum development about the fifth or sixth foetal month 

 (body length 25 — 30 cm). In older foetuses, as a rule, the processus 

 papillaris is somewhat retracted, so that the area papillaris of the 

 pancreas becomes relatively smaller. The relations in sagittal section 

 through a nearly full-term foetus are shown in Fig. 6, the processus 

 papillaris being in this case somewhat better developed than usual. 

 From this figure one can readily understand how, upon the gradual 

 upward retraction of the processus papillaris, the area papillaris of 

 the pancreas comes more and more into relation with the lesser 

 omentum, and through this with the left lobe of the liver, so that the 

 area papillaris of the foetal pancreas is gradually transformed into 

 the tuber omentale of the adult. At the time of birth, however, 

 there is almost invariably a more or less extensive area papillaris 

 present along the upper part of the anterior surface of the pancreas, 

 on the inner half of the body (Figs. 7, 8, ap). 



As Mettenheimer (10), Chievitz (5), and others have observed, 

 the posterior surface of the pancreas in the foetus is excluded from 

 contact with the kidney by the intervention of the large suprarenal 

 body. Although this statement holds good throughout the greater 

 part of foetal life, there seem to be exceptions in both the earliest 



