106 



BONES OF THE LOWER LIMB. 



The axis of the 2)eJris is the name given to a, line drawn at right 

 angles to the planes of the brim, cavity and outlet, through their 



ig. 94. — Vertical median Fig- 94. 



SECTION OF A FeMALE PeL- 



vis (reduced from Niigele's 

 llgure). i 



1, sympliysis ]}\\\ns ; 2, pro- 

 montory of the sivcriim ; 3, 

 coccygeal liones ; 4, anterior 

 superior spine of ilium ; 5, 

 tuberosity of ischium ; 6, 

 spine of ischium (the obtura- 

 tor foramen is not represented 

 so pi)iiited below as it gener- 

 ally is in females). The ver- 

 tical and horizontal lines in 

 the lower part of the tigure 

 will assist the eye in judging 

 of the degree of inclination of 

 the pelvis, as illustrated by 

 the next figure. 



central points. The pos- 

 terior wall, formed by 

 the sacrinn and coccyx, 

 being about five inches 

 long and concave, while 



the anterior wall at the symphysis pubis is only one and a half or two 

 inches long. The axis is curved ; it is directed at the inlet upwards 

 and forwards towards the umbilicus, and at the outlet downwards 

 and a little forwards. 



Fig. 95. — Sketch of part of the Fig. 95. 



Preceding Figure, showing 

 the Inclination of the brim 

 OF THE Pelvis and its Axis 

 in THE Erect Posture. 3 



a, h, line of inclination of the 

 brim of the true pelvis from 

 above the symphysis jjubis to the 

 pioraoutory of the sacrum ; e, f, 

 a line inclining backwards and 

 iipwards, touching the lower edgj 

 of the symjihysis pubis and point 

 of the coccyx ; c, d, axis of the 

 brim at right angles to the plane 

 of the brim ; d h r/, curved axis 

 of the cavity and outlet. 



Differences according 

 to Sex. — The size and 

 form of the })elvis differ 

 remarkably in the two 

 sexes. In the female the 

 constituent bones are more 

 slender and less marked 

 with muscular impressions; 



the ])erpendicular de[)th is less, and the breadth and capacity greater ; 

 the ilia are more expanded than in the male; the inlet of tli€ true 



