FACIAL MUSCULATURE OF THE JAPANESE 653 
In the Mongolians the differentiation of the muscle parts is 
very slight (figs. 1, 3, 4, 6, and 7). Birkner has observed an ap- 
parently united quadratus in a Chinese. In the negro the three 
distinct portions appeared in only three out of twenty-six indi- 
viduals. I have found this muscle divided into three parts 
three timesin the Japanese. Asarule, among Japanese the muscle 
likewise is fused into an entire muscle plate, so that the super- 
ficial layer, caput angulare and caput zygomaticus, and especially 
near the origin, the caput infraorbitale, covers it; if the former is 
more strongly developed, then the latter is entirely covered by 
it (in JII, JXIV). In the following lines the individual muscle 
portions are considered: 
The caput zygomaticum (M. zygomaticus minor) is well de- 
veloped and is never lacking in the Mongolians. In the negro 
(Chudzinski, Loth) the caput was absent in two out of forty- 
eight half faces (7.7 per cent), while, on the other hand, in 
Europeans (LeDouble) it was lacking twenty-two times in 100 
individuals (22 per cent). The separation of the caput from the 
M. orbicularis oculi is usually difficult, since the radiating bundles 
of the latter spread out over the surface of the so-called caput; 
only in the case of three Japanese was the head of the muscle 
perfectly distinct. 
The caput infraorbitale (figs. 1, 4, 5, 6, and 8) is strong in the 
Mongolians, coarse-fibered, and usually covers the caput zygo- 
maticum (figs. 3 and 6). The caput in the superficial layer in 
the case of two Chinese is strengthened by means of the orbicu- 
laris bundle (fig. 7); but I have never observed a caput divided 
into two distinct portions in the Japanese. The breadth at the 
point of origin is as follows: 
Japanese (Kudo) ca. 16 (10 to 26) mm. 
Europeans (Kudo) right 12, 26; left 12, 22, 21, 16 mm. 
Europeans (Chudzinski) 22 mm. 
Chinese (Kudo) right 23; left 25 mm. 
Negro (Chudzinski) 32 (22 to 39) mm. 
The caput infraorbitale is difficult to isolate from the other 
two capita in the case of the Mongolians (figs. 1, 6, and 7). The 
well-separated cases are divided into the following ratio: 
