178 
MASARU NAGAO 
TABLES 17 AND 18 
A Summary of the Mean Values Given in Tables 2-16 
TABLE 17 
Primates 
NAME OF SPEaES 
a 
/3 
7 
RADICS 
CENTER ANGLE 
INCLINATION ANGLE 
OF FOSSA MANDIB- 
ULARIS 
ARTICITLAR BASIO- 
NASAL ANGLE 
GNATHIC INDEX 
DENTAL INDEX 
degrees 
degrees 
degrees 
Simia satyrus 
4.4 
7.1 
10.6 
7.4 
35.6 
21.2 
25.2 
151 
54 
Man 
3.7 
5,8 
9.0 
7.6 
28.6 
34 1 
36.7 
101 
45 
Hylobates miiUeri 
2.1 
3.3 
5.3 
5.5 
22.8 
5.1 
27.2 
120 
40 
Macacus cynomolgus 
2.3 
3.9 
6.0 
6.0 
21.8 
8.4 
34.3 
135 
48 
Nasalis larvatus 
2.6 
3.4 
5.9 
7.8 
19.8 
5.9 
34.6 
122 
52 
Semnopithecus femoralis 
1.9 
2.8 
4.6 
5.9 
18.8 
10.4 
36.2 
106 
40 
Macacus nemestrinus 
2.7 
4.4 
7.0 
10.2 
16.3 
2.8 
45.4 
143 
55 
TABLE 18 
Artiodactyla 
Porcus babyrussa 
6.1 
7.9 
13.3 
11.2 
31.3 
28.8 
13.5 
205 
57 
Rangifer tarandus 
7.5 
10.2 
17.0 
17.1 
25.5 
15.7 
22.1 
218 
60 
Camelus bactrianus 
10.4 
13.9 
23.5 
24.0 
25.3 
24.5 
11.3 
178 
66 
Dicotyles sp 
5.9 
4.1 
9.9 
15.0 
23.9 
34.2 
163 
55 
5.5 
10.5 
15.4 
13.6 
23.4 
67.5 
18.8 
171 
46 
V. DETERMINATION OF THE INCLINATION OF THE FOSSA MANDIBULARIS 
It has been claimed by Spee that there exists a close dynamical 
relation between his curve and the inclination of the fossa, and a 
similar view has been held by some other authors. I have thought 
it desirable to examine this matter somewhat in detail. 
To study the inclination of the fossa it is first of all important to 
decide just what portion of the fossa should be taken. Since the 
purpose of the determination of the inchnation of the fossa is to pro- 
vide data for the discussion of the relation between this inclination 
and the movement of the jaw, and also between the former and the 
curve of Spee, the area of articulation within the fossa should be used 
for the determination of the inclination. This area extends from the 
