140 AMPHIBIA AND PISCES OF THE PERMIAN OF NORTH AMERICA 



making the formula, 2, 3, 3, 4, 3. The feet were clawless, the toes ending 

 rather bluntly. The foot as a whole, it is seen, is remarkable for its broad, 

 short form, and, because of the relatively large size of the tarsus, it must 

 have been very flexible. The absence of true claws, such as occur in some 

 of the Cotylosauria at least, and the Pelycosauria, is what we would expect. 

 The relatively short legs and broad feet were used exclusively in locomotion. 

 The front feet could not have been extended nearly as far forward as the 

 mouth and could have been of no possible use in seizing or holding the 

 animal's prey; and it is quite certain that the creatures did not need claws 

 for locomotion over soft ground. 



"In the restoration the front toes have been copied from the hind 

 ones, and it is not at all probable that there could have been much difi^erence 

 between them. That there were five fingers is shown conclusively, not only 

 from the carpus, but also from the front foot of Eryops, as figured by Cope, 

 a form which, in its skeletal structure, is closely allied to Trematops. The 

 radius also is given from the same figure by Cope. The fibula is in part con- 

 jectural, as is also the length of the tail. It is possible that the head was set 

 even more closely upon the shoulders. 



"From the absence of every indication in the matrix of a derm.al armor, 

 it is quite probable that the creature had a bare skin; and the absence of 

 claws and its short legs and feet indicate also that the animal lived not on 

 high, dry lands, but about the mud shores and in the water. The entire 

 absence of a neck, which is characteristic of all the lower vertebrates of the 

 Texas Permian, the large, ungainly but flattened head, the short body and tail, 

 and short, rather stout limbs, all must have given to the creature a very 

 bizarre aspect. 



"The distinction of Trematops from other genera of the rhachitomous 

 amphibians described from Texas seems certain. Its relationship with 

 Eryops is evident, but, aside from its smaller size and greater slenderness, 

 the structure of the head separates them widely. From Acheloma, which 

 I at first thought might be the same, there seem to be marked differences. 

 Cope's description of Acheloma leaves certain parts in doubt, parts of much 

 importance in the discrimination of the two genera, especially the size and 

 shape of the vacuities. He describes the premaxillary teeth as five in num- 

 ber and of large size, whereas in Trematops they are six in number and are 

 among the smallest of the whole series. He also states that the humerus 

 of Acheloma, a very remarkable thing for an amphibian, has an entepi- 

 condylar foramen, whereas there is no trace of such in the present form. 

 Dr. Matthew of the American Museum has very kindly compared the type 

 of Acheloma, at my request, and confirms these details, and also informs 

 me that the skull is different in shape from the figure sent him of Trematops. 

 I have no hesitation, hence, in giving to the present specimen the generic 

 name Trematops, chosen in reference to the numerous vacuities of the upper 

 side of the skull." 



