144 



THE SKELETON 



Blood-supply.— Tin- ilium receives on its anterior surface tAvigs from the iho- 

 luinl.ar, .hnp riniuulUx iliac, and obturator arteries. On the dorsum, arteries 

 enter it from the jrhiteal and sciatic trunks. ^ ^ . i • n 



The ischium is supplied l.y the obturator, mternal, and external circumflex. 



Picj ir,.-,.— Hip-bone, showing Secondary Centres. 



APPEARS AT FIFTEEN. UNITES AT TWENTY " 



APPEARS AT FIFTEEN. UNITES AT TWENTY 



THE LINES OF UNION ARE USUALLY OB- 

 LITERATED BY THE SIXTEENTH YEAR 



APPEARS AT SIXTEEN. FUSES AT TV.: ' ' ■ — i 



APPEARS AT FIHEEN. FUSES AT TWENTY 



Fig. 156.— Hip-bone (Inner Surface) at the Eighth Year. 



Till' pubes receives twigs from the obturator, internal and external circumflex, 

 deep e|)igastrie, and the jailiic branches of the common femoral artery. 



Development. — The cartilaginous representative of the hip-bone consists at first 

 of an ilio-ischiatic and a pubic segment. These quickly fuse and form a continuous 

 plate. ( lit (senbeig. ; Early in the second month a nucleus appears above the acetab- 

 ulum for the ilium, and one appears a little later below the cavity for the ischium. 



