THE MUSCLES OF THE LOWER EXTREMITY. 191 



its hinder margin ; from the inner line of the corresponding 

 postpubis ; and from the membrane filling in the ob- 

 turator space between these two elements. It is of a 

 subtriangular form, flat, and possesses a central tendon 

 to which its fibres converge in an oblique anterior 

 direction. AVheii this tendon reaches the obturator 

 foramen it becomes dense, subcylindricnl, and strong, 

 and passing through this vacuity it is inserted, in 

 common wdtli the gemellus, into the outer aspect of 

 the trochanter of the femur, opposite the insertion of 

 the gluteus 7nedius. Outside the pelvis the tendon of 

 this muscle lies upon the gemellus and is external to it. 



The late Professor Garrod made a point of calling 

 attention to the fact as to wdiether the area covered by 

 the origin of the obturator intenius was of an oval or 

 a triangular outline, and entered the information in his 

 valuable tables of the anatomical characters of birds. 

 It seems to me, however, that such a character as this 

 must bear with it but very little weight, as the form 

 of the muscle, so far as my observations go, varies 

 directly with the form of the pelvis, and particularly 

 with the form of the osseous elements to which it is 

 attached. 



About three years ago, I published an article entitled 

 '■ A Keview of the Muscles used in the Classification of 

 Birds" (see 124 of the Bihliography at the end of this 



Obturator internus. Owen, A2)teryx, p. 292 ; Reid, p. 143 ; Gurlt, 

 p. 28. 



„ „ Garrod. 



„ „ Quennerstedt, p. 14. ' 



,, „ Neander, p. 12. 



„ „ Watson, p. 108. 



Ahducteur interne de la cuisse. Milne-Edwards. 

 L' ohturateur externe. Gervais et Alix, p. 31 ; Alix, p. 434. 

 ]\[. obturator. Gadow, No. 19." 



