I30 AMERICAN PERMIAN VERTEBRATES 



perforating canal is at a greater distance from the distal ends of 

 the bones. In the distal row the bones are all decidedly larger 

 but have the same articulation. The centrale is well ossified, 

 separating the tibiale from the first tarsale, more broadly in front 

 than behind. 



The first metatarsal is a short, stout bone, about half the length 

 of the fifth, which is the longest of the series. It bears a single 

 rather long and stout phalange and a large claw. This toe was 

 probably divaricable in life. The fourth and fifth metatarsals 

 are not very different in length, but the fifth is the stouter. The 

 claws (Fig. 4) are large, much curved, and pointed, with a stout 

 inferior tubercle for the insertion of the flexor tendon. It is, of 

 course, assumed that the phalangeal formula is of the primitive 

 kind, as in Varanosaurus, and I do not think there can be doubt of 

 this, although the absence of three or four phalanges leaves the 

 positive proof of this for future investigation. If my arrangement 

 of these phalanges is correct the fifth toe is but little shorter than 

 the third. Altogether it is very certain that the foot was broader 

 and stouter than that of Varanosaurus and is nowise indicative of 

 climbing or even markedly cursorial habits. 



RESTORATION 



The mounted skeleton as shown in the frontispiece is, as has been 

 explained in the foregoing pages, a composite of three different 

 skeletons, Nos. 655, 656, 657. Of No. 655, from the base of the 

 tail to the seventh postcranial vertebra, the ribs, the scapulae, right 

 foreleg, left radius and ulna, pelvis, the right hind leg, and the left 

 femur. Of 656, the skull and first seven vertebrae; while the tail 

 is in part from another specimen. These various specimens in 

 the many bones they have in common agree perfectly in characters 

 and almost absolutely in size, so that the composition in nowise 

 affects the form and appearance of the skeleton. The parts shown 

 which are more or less conjectural are the first six or seven pairs of 

 ribs, the posterior clievron bones, the distal six caudal vertebrae, 

 and a few of the phalanges of both front and hind feet. The left 

 humerus, hand, tibia, fibula, and foot have been modeled after the 

 right ones. As has been explained there are other skeletons 



