The Development of the Alligator 307 
irregular; except at the extreme anterior end and 
at one or two other places, it lies in close contact 
with the floor of the neural tube. Directly under 
the notochord lies, in the posterior half of the figure, 
the large dorsal aorta (ao). The pharynx (ph), 
opening between the end of the forebrain and the 
thick mandibular fold (across which opening the 
amnion, a, of course extends), is a funnel-shaped 
. space which passes out of the plane of the section 
toward the posterior end of the figure. Its thick 
endodermal lining extends to the mandibular fold 
on the ventral side, while on the dorsal side it 
gradually thins out and becomes continuous with 
the thin ectoderm that extends over the forebrain. 
Just back of the mandibular fold is the bulbus (0), 
and back of that is the edge of the ventricle (vz). 
Posterior and dorsal to the ventricle the liver (2) 
is seen as an irregular mass of cells, and dorsal to 
the liver one of the Wolffian bodies (wé) is cut 
through its extreme edge. 
STAGE XIV 
FicureEs 17-17g (PLATES XXIII., XXIV.) 
Body flexure has increased until now the fore- 
brain and tail are almost in contact (Fig. 17). 
The eye has developed somewhat; the ear vesicle, 
which is not shown in the figure, is small and seems 
to lie nearer the ventral side; the nasal pit is much 
larger and is crescenticin shape. The hyomandib- 
