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MASARU NAGAO 
(1895) selected the line of occlusion.^ I selected the line of articu- 
lation, i.e., the line which is tangent to both the morsal surface of 
the superior central incisors and the disto-buccal cusp of the upper 
second molar, because the line selected by Tomes and Dolamore does 
not seem to me to be related to the occlusion, and the line selected 
by Walker and Gysi has the disadvantage that it must be determined 
from the lower jaw. 
My next attempt was to obtain the sectional surface along the 
median line of the fossa, as well as the line of articulation, projected 
on a sheet of paper. This was accomplished by the following method. 
To obtain the sectional surface along the median line of the fossa 
I have followed the method adopted by Tomes and Dolamore. These 
authors however did not state the exact portion of the fossa taken, 
so in order to show the sectional lateral view of the fossa I endeavored 
to determine the total length from the anterior margin of the area of 
articulation to thq top of the processus post-glenoidalis, which is a 
small conical process descending in front of the external auditory 
meatus {fig. 5, A-B). It was not however always possible to obtain 
the sectional view of the fossa by actual section from the museum 
specimens, so a modelling compound (dental) was advantageously used. 
A Hne {A-B,fig. 5) was drawn with a pencil along the fossa of the 
skull from the anterior margin of the area of articulation on the 
tuberculum articulare through the fossa to the top of the postglenoid 
process and then there were marked also with a pencil two points on 
this line; one at the point where it crosses the posterior margin of the 
area, and the other at the point where the posterior portion of the 
crest of the tuberculum articulare passes into the anterior wall of the 
fossa. Then the fossa was filled with modelling compound under 
gentle pressure. As soon as the modelling compound hardened, it 
was removed and cut into two pieces along the pencil line, which had 
been transferred to it from the skull. One of these pieces was re- 
fitted to the fossa again exposing the lateral aspect of the cut surface. 
A line {PQ, fig. 6) parallel to the line of articulation was then drawn 
and a deep cut was made with a knife along this line. At the same 
time the positions of the two marks made before on the fossa were 
^ The line of occlusion is tangent to both the morsal surface of the lower central incisors 
and the disto-buccal cusp of the lower second molar. 
