ALIMENTARY CANAL, ETC., OF AMIURUS CATUS. 407 
on the postero-inferior surface forms a line of division over which 
sometimes a lappet from the left stretches on the right half for a lit- 
tle distance. 
The lobes distinguishable on both halves, in the majority of cases 
observed, are as follows :— 
An antero-lateral lobe, not constant, stretching upward and back- 
ward ; it is generally long and slender. 
A postero-lateral, somewhat smaller than the preceding, and 
directed horizontally outwards. 
A postero-median, large, directed backward, that of the right side 
almost covering the gall-bladder. 
These lobes may or may not be the same in size for both halves, as 
a considerable amount of variation is always present. 
The lobulation on the surface of the liver in the cat-fish does not 
appear prominently or clearly. This is owing to the smallness of the 
lobules and to their passing almost without interruption into one 
another. In the gorged condition of the liver they can be easily 
seen as polygonal spaces, and measure about 0°5 mm. on the average. 
The gall-bladder is of elongated oval shape, with its long axis 
directed straight backwards. Anteriorly it passes into an arch-like 
cystic duct toward the middle line which receives 8-10 hepatocystic 
ducts in its course and becomes the ductus choledochus, at first large 
but decreasing in diameter backwards. It enters into the intestine 
in intimate connection with the pancreatic duct which lies above it. 
Both open separately, each on papille on the inner surface of the 
transversely ducted portion of the mid-gut, about two centimetres 
from the pyloric constriction. 
There are two coats to the liver. The outermost, the serosa, easily 
separable, is simply the peritoneal fold, and having all the characters 
of the mesenteric tissue. The other, more closely applied and inside 
the former, is apparently of flat epitheloid structures, hardly isolable 
from the close arrangement of the hepatic capillaries on which they 
lie. They may be analogous to the cortical cells described by 
Eberth' in the amphibian liver. 
The liver of the cat-fish is very poor in interlobular tissue. A fair 
amount enters the portal canal, but following the finer ramifications 
of the portal vein, the pancreas increases in volume, its acini twining 
1 Archiv fiir Mikr. Anat.—Bd. ITI., page 430. 
