MOODIE: PERMIAN ANPHIBIA. 249 



tero-inferior border is moderately thickened, and rounded; 

 gently concave along the proximal part and convex distally. 

 The antero-superior border is much thinner than the opposite 

 one, and is concave throughout the extent of the shaft, except 

 distally, where it is coossified with the procoracoid. The union 

 of these two bones is very close in this region, the sutural line 

 being distinguished with difficulty if at all. The procoriicoid 

 is narrower and more thickened below, reaching to the lower 

 part of the conjoined bone, and lying in close apposition though 

 not suturally united. Both the lateral surfaces of the scapula 

 are nearly flat. A little proximad to the narrowest part of the 

 shaft the bone is much thickened by a stout ridge on the inner 

 side, which includes between it and the remainder of the bone, 

 just back of or above the cotylus, a large, elongated foramen, 

 both of whose orifices can be seen from the inner side of the 

 bone only. 



"The glenoid surface is elongated and deeply concave in its 

 long diameter. The scapular portion is much smaller than the 

 coracoid, and is partly separated from it by a constriction ; 

 this surface is nearly flat and is placed at right angles to the 

 plane of the coracoid surface, looking directly downward when 

 the bone is lying horizontally. The rest of the cotylus is mod- 

 erately concave and looks outward and somewhat backward 

 and upward with the bone in its former position. Just how 

 much of the conjoined bone is formed of each element it is im- 

 possible to say since the union is so close that no trace of a 

 junction is perceptible. Evidently, however, the coracoid 

 forms only a small part of the whole bone. Its anterior or in- 

 ferior border is gently convex, the posterior one slightly 

 concave. 



"The anterior end of the superior border of the scapula is 

 gently convex, as is also the broad external surface. On the 

 inner side the foramen described above opens into a deep, 

 elongated, boat-shaped cavity at its distal end, the cavity 

 formed by the upper border of the ridge described. In the 

 lower or anterior end of the cavity there are apparently two 

 smaller foramina, the external orifices of which are just within 

 the anterior margin of the scapular face of the glenoid surface. 

 The proximal surface of the scapula is concave; that of the 

 coracoid, if the bone is limited by the ridge spoken of, is for the 

 most part gently convex and lies in a more mesial plane." 



a-Univ Sci. Bull.. Vol. V, No. 13. 



