Page:Mammalia (Beddard).djvu/607

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be insisted upon too strongly, as in some American Monkeys the face is as little projecting. Still we are now comparing Man with his undoubtedly nearest relatives the Simiidae. In the lower jaw the anterior line at the symphysis is an approximately straight one, that is at right angles to the long axis of the jaw, while Apes have a more retreating chin. The "beautiful sigmoid curve formed by the lumbar and dorsal vertebrae" is more pronounced in Man, but exists not only in the Anthropoids, but in other Apes.[1]

Fig. 282.—Foot of Man, Gorilla, and Orang of the same absolute length, to show the difference in proportions. The line a′a′ indicates the boundary between the tarsus and metatarsus; b′b′, that between the latter and the proximal phalanges; and c′c′ bounds the ends of the distal phalanges. as, Astragalus; ca, calcaneum; sc, scaphoid. (After Huxley.)

Fig. 283.—Skeleton of the left pes of a Chimpanzee. (Dorsal aspect.) as, Astragalus; cb, cuboid; cl, calcaneum; ec, ectocuneiform; en, endocuneiform; ms, mesocuneiform; nv, navicular; I-V, digits. (From Wiedersheim's Structure of Man.)

The fore-limbs are relatively short, the extreme length of the arm being such that the outstretched hand does not reach the knee. The thumb is a large and useful digit in Man, much more so than in the Anthropoids. On the other hand the hallux is not opposable. This is, of course, correlated with the upright attitude, as is also the greater relative thickness of that digit, upon which

  1. Cunningham, "Cunningham Memoirs," No. II. Royal Irish Acad. 1886.