672 MUSCLES OF THE PELVIS. 



one of these tubes is estimated at from eight to fourteen 

 days. The uterus has been preparing a membrane, the 

 decidua, which lines its internal surface by the time the 

 ovum arrives. That which covers the uterus is the decidua 

 vera; that which covers the ovum, the decidua reftexa. 

 The placenta is next seen, which is regarded as a joint pro- 

 duction of both the ovum and the mother. 



SECTION III. 



MUSCLES OF THE PELVIS. 



Glutens maximus. Dissection. Make an incision round 

 the crest of the ilium to the coccyx, extending downward 

 upon the outer side FIG. 212. 



of the thigh, about 

 three or four inches ; 

 make another incision 

 from the middle of the 

 crest of the ilium to 

 the trochanter ma- 



JOT. Dissect off the ^^BPHMRiil * 

 integuments, adipose 

 structure, and fascia, 

 in the direction of 

 the last incision, 

 which is the course 

 of the fibres of the 

 muscle, and which 

 will expose its whole extent. 



It arises from the posterior part of the crest of the ilium 

 from the contiguous dorsum of this bone, from the side of 



FIG. 212 represents the Muscles of the Pelvis on its exterior, a Posterior 

 urface of the sacrum. 6 Os-coccygis. c Crest of ilium, d Trochanter ma- 

 jor, e Linea aspera. / Gluteus maximus. g h Gluteus medius. i Vastui 

 externus. j Greater sacro-sciatic ligament, k Tuberosity of the ischium. i 

 Pyriformis. m Gemellus superior, o Gemellus inferior. Obturator inter- 

 nus. p Obturator externus. q Quadratus femoris. r Insertion of gluleuf 

 maximus. s Biceps femoris. t Semi-tendinosus. u Semi-membranosus. 9 

 Gracilis. 



