*Adaptation to Special Needs.*—When any single bone is studied in its relation to the other members of the group to which it belongs or with particular reference to its purpose in the body, its adaptation to some special place or use is at once apparent. Each bone serves some special purpose, and to this purpose it is adapted by its form and structure. Long bones, like the humerus and femur, are suited to giving strength, form, and stiffness to certain parts, while irregular bones, like the vertebræ and the pelvic bones, are fitted for supporting and protecting organs. Others, like the wrist and ear bones, make possible a peculiar kind of motion, and still others, like the ribs, are adapted to more than one purpose. The vast differences in shape, size, structure, and surface among the various bones are but the conditions that adapt them to particular forms of service in the body. TABLE IV - THE PRINCIPAL BONES AND THEIR GROUPING IN THE BODY I. AXIAL SKELETON A. _Skull_, 28. 1. Cranium, 8. _ a._ Frontal, forehead 1 _ b._ Parietal 2 _ c._ Temporal, temple 2 _ d._ Occipital 1 _ e._ Sphenoid 1 _ f._ Ethmoid 1 2. Face, 14. _ a._ Inferior maxillary 1 _ b._ Superior maxillary 2 _ c._ Palatine, palate 2 _ d._ Nasal bones 2 _ e._ Vomer 1 _ f._ Inferior turbinated 2 _ g._ Lachrymal 2 _ h._ Malar, cheek bones 2 3. Bones of the Ears, 6. _ a._ Malleus 2 _ b._ Incus 2 _ c._ Stapes 2 B. _Spinal Column_, 26. 1. Cervical, or neck, vertebræ 7 2. Dorsal, or thoracic, vertebræ 12 3. Lumbar vertebræ 5 4. Sacrum 1 5. Coccyx 1 C. _Thorax_, 25. 1. Ribs 24 2. Sternum 1 D. _Hyoid_, 1 (at base of tongue). II. APPENDICULAR SKELETON A. _Shoulder girdle_ 4. 1. Clavicle, collarbone. 2 2. Scapula, shoulder blade 2 B. _Upper extremities_, 60. 1. Humerus 2 2. Radius 2 3. Ulna 2 4. Carpal, wrist bones 16 5. Metacarpal 10 6. Phalanges of fingers 28 C. _Pelvic girdle_, 2. 1. Osinnominatum 2 D. _Lower extremities_, 60.