500 Pancreas in Embryos of the Pig, Rabbit, Cat, and Man 
nates distally in the hepatic and cystic ducts (D. hep. and D. cyst.), the 
latter passing to the ventrally placed gall bladder (Ves. fel.). The ven- 
tral pancreas (Panc. v.) is a small solid mass of cells arising from the 
posterior wall of the common bile duct, close to its union with the intes- 
tine. It extends posteriorly and a little to the right, but is still consid- 
erably removed from the ventral border of the portal vein. 
The second model (Fig. 6) is from an embryo of 13.6 mm. (H. E. C. 
839). It is evident that this is a much more advanced condition than 
that just described. The model is here represented, somewhat ventrally, 
from the right side. The stomach (St.) has so revolved that its primi- 
tive dorsal border or greater curvature is now toward the left, and its 
ventral border or lesser curvature toward the right. 
The dorsal pancreas (Panc. d.) is very large as compared with the 
ventral pancreas (Panc. v.). Its duct (D. panc. d.) opens into the duo- 
denum nearer the stomach than the bile duct (D. chol.), as was shown in 
the younger embryo. Distally it extends into the mesogastrium. There 
is, however, no process encircling the right side of the portal vein such 
as was found in the pig and rabbit embryos, the condition being more 
like that in the cat of 10.7 mm. 
The ventral pancreas (Panc. v.), which in the drawing is more darkly 
shaded than the dorsal pancreas, forms only a very small part of the pan- 
creatic tissue. By the growth of the duodenum the ventral pancreas has 
been carried into close relation with the proximal part of the dorsal pan- 
creas as happened in the pig embryo (Fig. 2). The two parts of the 
pancreas (Panc. d. and v.) already anastomose ventral to the portal vein 
and on the left of the common bile duct. 
The duct of the ventral pancreas (D. panc. v.) is well developed at this 
stage, and according to Hamburger, 92, Schirmer, 93, Joubin, 95, 
Charpy, 98, Helly, 98, Opie, 03, and Baldwin, 07, its absence is excep- 
tional in the human adult. Thus these investigators confirm the earlier 
opinion of Santorini and Bernard. 
The human pancreatic ducts differ from those of other mammals studied 
in that usually the duct of the dorsal pancreas opens into the intestine 
nearer the stomach than the common bile duct; in other mammals the 
duct of the dorsal pancreas is beyond the bile duct. Even in young 
human embryos the dorsal pancreas is distinctly anterior to the intestinal 
orifice of the bile duct (Fig. 5; Felix, Fig. 18, Taf. XVII; Helly, Fig. 
30, Taf. XVII; Kollmann, Fig. 394; Ingalls, Fig. 3 u. 4, Taf. XXX; 
etc.). Several cases, however, are recorded both in the embryo (His, 
85, Wlassow, 94, Janosik, 95, Volker, o2 and 03, et al.), and in the 
