104 



AMPHIBIA AND PISCES OF THE PERMIAN OF NORTH AMERICA 



activity. The habits of the creature can hardly be in doubt. The superior 

 position of eyes and nostrils shows that it lay nearly submerged until some 

 prey came within reach, when a sudden rush with its very capacious mouth 

 extended ended in the engulfment of the prey. The coprolites show remains 

 of fish and amphibian bones (Neumeyer, 63). 



Parioxys ferricolus and Anisodex imbricarius Cope. 



So little is known of these forms that the discussion of their morphology 

 must await future discoveries. 



Genus ACHELOMA Cope. 

 Acheloma cumminsi Cope (page 34). (Plate 11.) 



Characteristic specimen: The type No. 4205 Am. Mus. 



The original description of this genus and species is good; a few points 

 are added. The skull is incomplete, and there is considerable plaster in the 

 facial and postorbital regions, where vacuities occur in Trematops Williston, 

 which the skull resembles in many respects; but the two are distinct. The 

 skull is higher in the cranial region than Eryops, and there is a decided 

 preorbital contraction. The sutures can not be made out. 



Fig. 34. — Acheloma cumminsi. No. 4205 Am. Mus. X J^. 



A. Lateral view of right scapula. 



B. Anterior view of same. 



C. Lateral view of four dorsal vertebrje. 



D. Diagrammatic anterior view of a dorsal vertebra. 



E. Ulna. 



F. Radius. 



G. Anterior view of right humerus. 

 H. Posterior edge of same. 



The scapula presents a most remarkable appearance, which attracted 

 Cope's attention (see original description). In the present position of the 

 scapulae, which is evidently a little too high, the blade is set at an angle of 45° 

 to the vertical and overlies the back; the coracoid portion is also at an angle 

 of 45° from the vertical, so that the two parts of the scapula are at right 

 angles to each other (see fig. 34, a and b). The blade is elongate and rather 

 wide; the posterior end is thick and shows extensive cartilaginous attach- 

 ment. The upper edge is thin and the lower thick and rounded. From a 

 point near the middle of the lower edge, a process runs directly inward to 

 support the coracoid portion, which lies at right angles to the scapulcc (see 

 fig- 35 b)- The lower edge is continued forward on the outer surface of 



