192 



THE MYOLOGY OF THE RAVEN. 



volume), in which I made certain remarks upon " the 

 area of the origin of the obturator internus." As they 

 bear upon what I have just said in the last paragraph, 

 they will be of value for comparison in the present con- 

 nection, and so are here republished : this applies more 

 particularly to the figure (53 bis), also given, as it repre- 

 sents the parts in question as they occur in that curious 

 bird the Pinon Jay, one of the Corvidce of the western 



FIG. 53 bis. Eight three-quartering view of the pelvis of a specimen of the 

 Pinon Jay (Cyanocephalus cyanoecphalus), showing the origin of the 

 obturator internus muscle of the right side, o.i. Drawn by the author 

 from the specimen, and somewhat enlarged. 



part of the United States. In the paper to which I 

 have just referred, I said, substantially, of the obturator 

 internus, that " In birds this muscle arises, as shown in 

 the figure, from the ventral surface of the pelvis, its 

 fibres being attached to the post-pubic bone and the 

 ischium. As a rule it is a bipenniform muscle, its fibres 

 being directed forwards, but at the same time, on either 



