BONES OF THE L'PPER LIMB. 81 



" On Synostotic Crania," 1865 ; W. Turner, " On Cranial Deformities," in Nat, 

 Hist. Re\aew. 1864.) Another series of irregular foi-ms of skull is that produced 

 hy pressiu'e artificially applied in early life, and is best exemplified from among 

 those American tribes who compress the heads of their children by means of an 

 apparatus of boards and bandages : it is also illustrated in a slighter degree by 

 individual instances in which undue pressure has been employed imintentionaUy. 

 (Gosse, '• Essai sur les Defomiations artificielles du Crane," 185.5.) Posthumous 

 distortions likewise occur in long-bui'ied skulls, subjected to the combined 

 influence of jjressure and moistui'e. (Wilson, " Prehistoric Annals of Scotland.") 



IV.— BOISTES OF THE UPPER LIMB. 



The upper limb consists of the shoulder, the arm, hmchhmi, the 

 forearm, antihrachium, and the hand, manus. The bones of the 

 shoulder are the scapula and clavicle, which together form the pectoral 

 arch or shoulder girdle ; in the arm is the humerus ; in the forearm 

 are the radius and ulna ; and in the hand three groups of bones, the 

 carpus, metacarpus, and digital phalanges. 



SCAPULA. 



This bone is placed upon the upper and back part of the thorax, 

 occupies the space from the second to the seventh rib, and forms the 

 posterior part of the shoulder-girdle. It is not attached directly to 

 the trunk, but is articulated with the outer end of the clavicle, and 

 from it is suspended the humerus in the shoulder-joint. 



It is an irregular flat bone of a triangular form, its surfaces are 

 anterior and posterior, its borders superior, internal, and external, and 

 its angles superior, inferior, and external. 



The anlerior surface presents a shallow concavity, the fossa^dscapu- 

 laris or venter, occupied by the subscapularis muscle, audT markeU by 

 (tAvJL'ogular prominent lines converging upwards and outwards, which give 

 attachment to the tendinous intersections of that muscle. Separated 

 from this concavity, there are several smaller flat spaces ; one is a 

 triangular surface in front of the superior angle, another is a smaller 

 surface at the inferior angle, and these, together with a rough line 

 running close to the -pesterror border and uniting them, give attach- 

 ment to the serratus magnus muscle. 



The posterior surface or dorsum is divided by the spine into two 

 unequal parts, the superior and smaller of which is called fossa sKprci- 

 spinata, the inferior fossa infraspinata. The supraspinous fossa is 

 occupied by the supraspinatus muscle. The infi-aspinous fossa, much 

 larger than the preceding, presents in the middle a convexity cor- 

 responding to the concavity of the venter, and outside this a con- 

 cavity bounded by the prominent external border. It is marked near 

 the inner border- by short lines, corresponding to tendinous septa of the 

 infraspinatus muscle, and is occupied by that muscle in the greater 

 part of its extent. Adjacent to the external border, in its middle third, 

 is a narrow interval giving attachment to the tei'es minormnsiile^ ; ^nd 

 beneath this, extending over the inferior angle, is a ralsecToval surface, 

 from which the teres major arises. These spaces are separated from 

 that of the infraspinatus muscle by a rough line, which gives attach- 

 ment to an aponeurotic septum. 



VOL. I. (J 



