CURVE OF SPEE IN MAMMALS 
179 
middle portion of the posterior wall of the fossa to the anterior portion 
of the tuberculum articulare, and laterally from the lateral portion 
of the fossa to the anterior portion of the Glaserian fissure. Further- 
more, this area presents its greatest width at the transitional portion 
of the anterior wall of the fossa to the tuberculum articulare. 
It is evident that when the occlusion of the jaws is in the so-called 
"resting bite," the upper anterior portion of the condyle rests on the 
anterior wall of the fossa, that is, on the concavity of the area of 
articulation mentioned above, separated only by the meniscus finter- 
articular cartilage), while the posterior aspect of the articular surface 
Fig. 5. Drawing Showing, in Dotted Lines, the Area Over WntCH the Upper 
Anterior Portion of the Articular Surface of the Condyle Slides 
Showing the line AB drawn from the anterior margin of the area to the top of the pro- 
cessus postglenoidalis. 
of the condyle is not in contact with the wall of the fossa. If the 
forward excursion of the lower jaw while in sliding contact starts 
from the resting bite, the condyle slips downward and forward to the 
crest of the tuberculum articulare in contact with the concavity of 
the area. In other words, in the case of sliding contact, the sliding 
between the condyle and the fossa by the forward excursion of the 
lower jaw is done principally in the concavity of the area. 
It is now necessary to select a base line from which the angle of 
the inclination may be determined. Tomes and Dolamore ('01) 
selected a line parallel to the line drawn from the anterior nasal spine 
to the floor of the external auditory meatus, while Walker and Gysi 
