ANATOMY. 



restricted to two directions, as in the hinge 

 of a <1< 



Tin.- skeleton consists of an assemblage. 

 of all the bones in the body, excepting the 

 os hyoides. It is said to be a natural ske- 

 leton when the bones are connected .by 

 means of their own ligaments or curtila- 

 ges ; an artificial one, when wire or 

 other extraneous substances are employ- 

 ed. 



It is divided into the head, trunk, and 

 extremities. 



The head consists of the cranium and 

 the tare. The former of these partscon- 

 sists of 1 or 2 ossa frontis ; 2 ossa parieta- 

 lia ; 1 os sphenobasilare ; 2 ossa tempo- 

 rum ; 2 mallei ; 2 incudes; 2orbicularia; 

 2 stapedes ; and 1 os xthmoidcum : on 

 the whole, of 15 or 16 bones. 



The face has 2 ossa maxillaria superi- 

 pra ; 2 ossa palati ; 2 ossa nial.v ; 2 ossa 

 nasi ; 2 ossa lacrymalia or uncuis ; 2 ossa 

 tiirhinata inferiora ; 1 os vomer ; 1 max- 

 illa inferior ; 32 teeth ; on tlie whole, 46 

 bones. 



The os hyoides consists of a body, 2 la- 

 teral portions called cornua, and 2 surul 

 processes called appendices. 



The bones of the head arc therefore 61 

 or 62 ; with the os hyoides 66 or 67. 



In the neck there are 7 cervical verte- 

 brae; in the chest 12 dorsal vertebrae ; 24 

 ribs ; 2 or 3 bones of the sternum; in the 

 loins 5 lumbar vertebra:; in the pelvis 1 

 sacrum, 4 ossa coccygis, 2 ossa innomi- 

 nata. 



Therefore the whole trunk has 57 or 58 

 bones. 



The shoulders have two clavicles, and 

 2 scapulae; the arms 2 humeri ; the fore- 

 arms 2 ulna: and 2 radii ; the wrists 2 os- 

 vi scaphoidea; 2 ossalunaria; 2 ossa 

 cuneiformiu; 2 ossa pisiformia; 2ossati:i- 

 pe/.ia; 2 ossatrape/.ioidea ; Jossamagna; 

 2 ossa unciformia; the metacarpi lOmeta- 

 oarpal bones ; the fingers 10 posterior 

 phalanges, 8 middle phalanges, 10 ante- 

 rior phalanges, and 8 scsamoid bones. 



The bones of the upperextremities arc 

 in the whole 72. 



The thighs have 2 femora; the legs 2 

 palellse, and 2 tilnil.v ; the tarsi 2 

 astr.igali, 2 ossa raleis, 2 ossa na\ icularia, 

 6 cuneiform bones, 2 ossa cuboidea ; the 

 metatarsi 10 metatarsal bones ; the toes 

 10 posterior phalanges, 8 middle phalan- 

 ges, 10 anterior phalanges, and 6 scsamoid 

 bones. 



The bones of the lower extremities 

 are 66. 



The whole skeleton contains 259 or 261 

 bones. 



Of the bones just enumerated, the os 

 frontis, spheno-occipitale, ethmoideum, 

 vomer, inferior maxilla, the 

 crum, and os coccygis, the bones of the 

 sternum, and the os linguale medium, or 

 body of the os hyoides, are single bones ; 

 and being placed in the middle of the !>o- 

 consequently symmetrical. Of all 

 the other bones, there is a pair, consisting 

 of a bone for the right, and another for 

 the left side. 



The structure of the whole skeleton is 

 therefore symmetrical ; since an imagina- 

 ry perpendicular line drawn through tin- 

 whole would divide even thesingle bones 

 into a right and a left half, exactly resem- 

 bling each other. This observation must 

 however be taken with some allowance ; 

 since the corresponding bones of one side 

 are not always perfectly similar to thos 

 of the opposite ; nor do the two halves <,r' 

 the single bone.s always exactly agree in 

 form, &c. 



The entire natural skeleton of a man of 

 middle stature, in a dried state, 

 from 150 to 200 ounces ; that of a woman 

 from 100 to 160 ounces. 



Bones of the liead. The cranium is the 

 oval bony cavity containing the brain ; 

 the face is placed at the anterior and low- 

 er part of this cavity, and holds some of 

 the organs of sense, and the instruments 

 of mastication. 



The bones of the head are joined by 

 sutures, a mode of union nearlv peculiar 

 to themselves ; hence, when all the soft 

 parts are destroyed by maceration, they 

 still remain most firmly connected to each 

 other, excepting the front teeth and the 

 lower jaw. The sutures are formed by 

 numerous sharp and ramified pi. 

 of the opposed edges of the diiTerent 

 bones, shooting into cm-responding vacui- 

 ties of each other, in some insiances, 

 however, the bones seem to be joined by 

 the opposition of plane surf'icos, and here 

 the union appears externally like a mere 

 line, instead of the irregular zigzag course 

 which it takes in the former case The 

 last mentioned junction is called har- 

 monia. 



In the fcctal state, the bones of the cra- 

 nium do not touch each other, ;> 

 separated by considerable intcn tl-, of 

 membrane, and have thin extenuated 

 margins, which allow them to ri<i 

 each other when Subjected to pressure. 

 Tile larger and more conspicuous of these 

 intervals are called fontanelli s. and allow 

 of the pulsation of the brain being felt in 

 a young subject. The importance of this 

 ing- the head to accom- 



