CHONDROCRANIUM OF EUMECES 139 
the foramina of the otic region, and the columella auris, which 
may be conveniently discussed in connection with this region, 
whatever its real homologies. 
2. Exterior of auditory capsule 
As already noted, the cochlear portion of the auditory capsule 
is relatively much larger in Eumeces than in Lacerta. As a con- 
sequence, the general form of the capsule is strikingly different 
in the two animals, as seen from figure 32, in which the capsules 
of Eumeces (solid lines) and Lacerta (broken lines) are combined. 
The outline for Lacerta is derived from Gaupp’s figure 7, that 
for Eumeces from figure 8 of this paper. In Lacerta the general 
form is a horizontal oval, with the larger end to the posterior 
and the long axis extending from posteromedial to anterolateral; 
the ventral contour of the oval is somewhat irregular because of 
the protrusion of the cochlear prominence. On the other hand, 
in Eumeces the cochlear prominence is so exaggerated as to give 
to the entire capsule a pear-shaped outline (fig. 7), in which the 
slender stem end (cochlear prominence), extending downward 
and forward, determines a new long axis. While the long axes 
of the two capsules in Lacerta and the corresponding axes of 
their upper utriculosaccular portions in Eumeces diverge an- 
teriorly (fig. 1), the new long axes in Eumeces are almost exactly 
parallel to the sagittal plane of the head. A further relative in- 
crease in the size of the cochlear portions of the capsules might 
well lead to the anterior convergence characteristic of the Mam- 
malia. As seen from the front, the capsule of Eumeces has rather 
the form of a half pear, the median contour being approximately 
plane, while the lateral contour, especially in the upper utriculo- 
saccular portion, is conspicuously convex. 
Aside.from the contrast in form resulting from unequal devel- 
opment of the cochlear prominence, the superficial topography 
of the otic capsule agrees very closely in Eumeces and Lacerta. 
On the lateral surface (fig. 7) the prominences corresponding to 
all three of the semicircular canals are recognizable, the anterior 
