Fig. 16. 10, 10, 10, The metacarpal bones of the hand. 11, 11, First range of finger-bones. 12, 12, Second range of finger-bones. 13, 13, Third range of finger-bones. 14, 15, Bones of the thumb.
103. The METACARPUS is composed of five bones, upon four of which the first range of the finger-bones is placed; and 42 upon the other, the first bone of the thumb. The five metacarpal bones articulate with the second range of carpal bones.
101. The radius. 102. How many bones in the carpus? How are they ranged? 103. Describe the metacarpus.
104. The PHALANGES of the fingers have three ranges of bones, while the thumb has but two.
Observation. The wonderful adaptation of the hand to all the mechanical offices of life, is one cause of man’s superiority over the rest of creation. This arises from the size and strength of the thumbs, and the different lengths of the fingers.
105. The LOWER EXTREMITIES contain sixty bones—the Fe´mur, (thigh-bone;) the Pa-tel´la, (knee-pan;) the Tib´i-a, (shin-bone;) the Fib´u-la, (small bone of the leg;) the Tar´sus, (instep;) the Met-a-tar´sus, (middle of the foot;) and the Pha-lan´ges, (toes.)
106. The FEMUR is the longest bone in the system. It supports the weight of the head, trunk, and upper extremities. The large, round head of this bone is placed in the acetabulum. This articulation is a perfect specimen of the ball and socket joint.
107. The PATELLA is a small bone connected with the tibia by a strong ligament. The tendon of the ex-tens´or muscles of the leg is attached to its upper edge. This bone is placed on the anterior part of the lower extremity of the femur, and acts like a pulley, in the extension of the limb.
108. The TIBIA is the largest bone of the leg. It is of a triangular shape, and enlarged at each extremity.