24 



ANATOMY FOE NUESES. 



[CHAP. IV. 



FIG. 15. THE SKELETON, a, parietal 

 bone; 6, frontal; c, cervical vertebrae; d, 

 sternum ; e, lumbar vertebrae ; /, ulna ; g, ra- 

 dius ; h, wrist or carpal bones ; i, metacarpal 

 bones; fc, phalanges; I, tibia; m, fibula; n, 

 tarsal bones; o, metatarsal; p, phalanges; 

 q, patella; r, femur; s, haunch bone; t, 

 humerus; u, clavicle. 



cavities and to support and 

 protect the organs contained 

 in these cavities. The bones 

 of the extremities enclose no 

 cavities, and are chiefly used 

 in the upper extremity for 

 tact and prehension, and in 

 the lower for support and 

 locomotion ; in both situa- 

 tions they form a system of 

 levers. If the surface of any 

 bone is examined, certain 

 eminences and depressions 

 are seen, which are of two 

 kinds : articular and non- 

 articular. Non-articular pro- 

 cesses and depressions serve 

 for attachment of ligaments 

 and muscles ; the articular 

 are provided for the mutual 

 connection of joints. 



Long bones. A long bone 

 consists of a lengthened 

 cylinder or shaft and two 

 extremities. The shaft is 

 formed mainly of compact 

 tissue, this compact tissue 

 being thickest in the mid- 

 dle where the bone is most 

 slender and the strain great- 

 est, and it is hollowed out 

 in the interior to form the 

 medullary canal. The ex- 

 tremities are made up of 

 spongy tissue with only a 

 thin coating of compact sub- 

 stance, and are more or less 

 expanded for greater con- 

 venience of mutual connec- 

 tion, and to afford a broad 



