PALZONTOLOGICAL NOTES 259 
portion is preserved and it is evident that it does not differ 
materially from the form figured) by Cope in) 1856.) Phe 
expanded end is very thin and the edges ended in digitate 
expansions. The posterior elongation is thicker in the middle, 
but thins out at the edges. 
The clavicles are peculiar bones, widely expanded at the 
inner extremity where they overlap the interclavicle and with 
almost rectangular anterior inner corners. Toward the outer 
extremities they come almost to a point and in life overlay the 
middle portion of the scapula. The whole bone is slightly 
curved to conform to the girdle and is thin and plate-like at the 
inner portion and stouter and more rod-like distally. The 
prominence near the middle of the distal side is rugose and 
evidently served for ligamentous attachment. 
The scapula and epicoracoid of one side are preserved 
almost complete and in the natural curvature; the coracoid is 
equally well preserved, but, as is common, separated from the 
others. (In the figure of the thoracic girdle the scapule appear 
slightly too long as in the representation on the flat the curva- 
ture does not appear.) The bones are quite similar to those 
figured in the papers cited, but the epicoracoidal edge is more 
rounded; the whole epicoracoid is very thin. The suture 
between the epicoracoid and scapula runs through the middle of 
the articular face for the humerus and then fades out into an 
almost complete anchylosis of the bones near the anterior edge. 
Fig. 6, Plate II, shows the scapula and epicoracoid without the 
coracoid in profile, giving a good idea of the curvature of the 
shoulder girdle. 
The pelvis of the Pelycosauria has not previously been made 
out. Cope described what he considered to be the pelvis of 
Dimetrodon, but later discoveries showed it to be the pelvis of the 
amphibian Avyops. The same specimen which furnished the 
thoracic girdle described above affords an almost perfect pelvis. 
The bones are preserved in the same refractory iron-sand cement 
as the rest of the specimen and the slender edges of the bones 
have suffered accordingly, but the main portion of the bones 
