rt of caecum, to be seen in the next stage of
development.

The duodenum, _d_, makes a U-shaped bend at the side of the stomach, and
then, in the region of the caudal edge of the gizzard, _gz_, dips
suddenly ventrad and caudad towards the umbilical cord, _u_, where it
apparently ends blindly, though this appearance is probably due to an
artifact in the embryo from which the reconstruction was made. It is
likely that, in removing the embryo from the yolk, the connection
between the two loops, _i_, of the intestine was broken.

The ascending intestinal loop is of slightly less caliber than the
descending loop above mentioned; it passes dorsal and cephalad to the
posterior border of the gizzard where its lumen is continuous, for a
short distance, with that of the descending loop above described. This
unusual condition is probably abnormal, but owing to lack of material
only one series of this stage was studied.

At the dorso-caudal angle of the gizzard the small intestine, _i_, opens
into the ventral side of a larger tube which may be called the large
intestine, _il_. The blind end of the large intestine, cephalad to the
opening of the small intestine, projects forward, dorsal to the gizzard,
as a sort of caecum, _ce_, though this structure is generally stated to
be wanting in the crocodilia, and is not seen in the next stage.

From the caecum the large intestine passes in a ventro-caudal direction,
with gradually decreasing caliber, to the cloaca, from whose anterior
wall the intromittent organ, _io_, projects.

From the ventral wall of the large intestine, at a point about one-third
the distance from the cloaca to the caecum, projects ventrad and
cephalad the stalk of the allantois, _al_. Owing to its thin walls and
small lumen the allantois was traced only a short distance into the
umbilical stalk.

The profile of the liver, _li_, has, at this stage, about the same area
and even outline as that of the lung. It lies, of course, on both sides
of the enteron proper, and overlaps, anteriorly, as has been said, the
posterior end of the lung.

Figure 7A represents a section through the plane 305 of figure 7.
A considerable advance in the general development of the organs is seen
over the last stage studied. The spinal column is well outlined in
cartilage, and the ribs are cut at various places, _r_. In the body wall
a considerable differentiation of muscular tissue has taken place, but
it is only faintly shown in this