22 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. // 



both fore- and hindfeet are short and rounded without trace of 

 claws, though they may have been terminated by blunt, rounded 

 nails. In all, there are on the two slabs 45 tracks about equally 

 divided among the four feet of the animal. 



The creature making these tracks was apparently a short, squat 

 quadruped with a wide body, and evidently slow of movement as 

 indicated by the short stride. There is no evidence of a tail drag on 



Fig. 15. — Restoration of Trematops ■milleri Williston. An 

 amphibian from the Permian of Texas. (After Williston.) 



either of the slabs. The forefoot impression is always placed in front 

 and slightly outside the hind. 



In reviewing the known Permian animals in search of the pos- 

 sible makers of these tracks, two forms were found, Cacops aspi- 

 dephorus and Trematops milleri,'' either of which appears to have 

 the proper proportions to leave a trackway similar to the one under 

 discussion, both being relatively short, wide bodied creatures with 

 short, stubby tails and large five-toed feet without claws (see figs. 



^ Williston, S. W., Journ. Geol., Vol. 22, 1914, pp. 61-62. 



