142 



THE SKKLKTOX 



externum. To its inncT surface the eras penis is attached; it also gives origin to the 

 transrcrsd.s prrinci, the enrtor peni.s, and the obturator internus. 



Tin- pubes consists of a body an.l two rami. The hody, quadrilateral in shai)e 

 i< continuous with tlie ramus of the ischium l)y means of a flattened process termed 

 the descending ramus. The outer surface of the Ixxly gives origm to tlie (Khhx'tnr 



Yui. 15:}. — An Immatcre IxxoMtx at;: I'.oxe. siiowinc a Corvi.oin I'.oxk. 



THE COTYLOID BONE 



lonyii-i. The adductor brevis, the gracilis, and the obturator e.rtcrnu--< arise from the 

 outer surface of the body and descending ramus. A small portion of the adductor 

 magnus also arises from the descending ramus. The posterior surface of the body 

 and that of the descending ramus is continuous with the corresponding surface of 

 the ramus of the ischium, and affords attaehment to the levator ani and obturator 



Fig. lot. — Thk Pelvis of a Fcetus at Bikth, to show the Three Portions of the 



IXXOMIXATE P.OXKS. 



THE NUCLEUS FOR THE ILIUM APPEARS 

 EARLY IN THE SECOND MONTH 



THE NUCLEUS FOR THE PUBES APPEARS ABOUT 



THE END OF THE FOURTH MONTH 

 THE NUCLEUS FOR THE ISCHIUM APPEARS IN 

 THE THIRD MONTH 



internum. Tht- posterior surface of the descending ramus gives origin to the coiii- 

 presmr uretlrnv and a part of the erector penia^ the C7iis peni.-i, and the obturator 

 internus. The inner l)order is rough and covered with fibro-cartilage, which unites 

 it with the opposite V)one to form the })ubic sgmphi/xis. The outer l)order forms part 

 of the obturator foramen. The inner border of the descending ramus forms with 

 the ramus of the ischium the pubic arch. 



