diameter of
the oesophagus. As has been said it ends blindly at a point a short
distance anterior to the antero-ventral edge of the liver. A few
sections caudad to the one under discussion the bile duct connects with
the liver, figure 6A, _bd'_; and some distance caudad to this the duct
opens, _bd''_, into the duodenum so close to the opening, _pan'_, of the
pancreas that it is difficult to determine whether the latter organ has
a separate opening into the duodenum or opens into the bile duct.

At some distance ventrad to the structures just described the intestine
is cut, by the plane of the section, in two places, _i_. The more dorsal
of these is inclosed and has, under this magnification, the same
appearance as the duodenum, _d_; a higher magnification, however, shows
that its epithelium consists of a single layer of tall, rather clear,
columnar cells. The more ventral of the two sections, above mentioned,
which is continuous with the dorsal section a very short distance caudad
to this point, is in the region that opens to the yolk--in fact a number
of yolk-granules, _y_, may be seen in the opening. The epithelium of
this part of the intestine consists of a single layer of clear, columnar
cells, which, around the borders of the opening, are thrown into
numerous folds and are almost of goblet form.

Figure 6H represents a section through the plane 820 of figure 6A. The
section is caudad to one lung and cuts the extreme tip of the other,
_lu_. The liver, _li_, and pancreas, _pan_, are seen at the side of the
stomach, _i'_, here cut through its greatest transverse diameter. The
epithelium of the stomach varies somewhat in thickness and consists of
two or three layers of cells, the variation in thickness being due to a
variation in the length of the cells rather than to a variation in the
number of layers.

Ventrad to the stomach the intestine, _i_, is cut in three places, of
which the most dorsal section is the largest. The epithelium of these
intestinal sections, especially the lower two, consists of usually a
single layer of columnar cells which are clearer than those of the
stomach. A fairly thin mesentery, _ms_, supports this region of the
intestine.

In the region of the posterior appendages, _pa_, the section passes
through the hindgut, _hg_, and allantois, _al_. The former is of about
the same size as the more anterior sections of the intestine, but its
epithelium is less clear and is composed of two or more