REPTILIA : SEYMOURIA 



SI 



finally occurred. One thing is evident, the skeleton had been 

 subjected to but very slight or no disturbance from wind, waves, 

 currents, or predatory animals after death. Nor do the parts of 

 the skeleton show distortion or compression, as is so often the case 

 with bones in this and other formations. 



Skull. — The skull is very perfectly preserved, the short exposure 

 of the cranial table had injured it but shghtly, and in no wise 

 affected its shape; unfortunately, however, it prevents the certain 

 corroboration of the sutures 

 observed by Broili, a matter 

 of less regret since the well- 

 preserved skulls studied by 

 him, at least in this region, 

 apparently leave little or no 

 doubt as to the structure. 

 The teeth also, because of 

 their extreme delicacy, could 

 not be worked out entire 

 from the hard matrix. This, 

 however, is not to be greatly 

 regretted, since between the 

 two sides one is able to de- 

 termine the dentition quite 

 satisfactorily, in the upper 

 jaws at least. In the outline 

 figure I have inserted those 

 sutures copied from BroiU's 

 drawings in dotted Knes, while 

 those satisfactorily determined in this specimen are shown in con- 

 tinuous Hnes; others about which I am uncertain I have figured 

 in lines of small crosses. 



The skull is elongate, triangular in shape, nearly flat on the 

 upper surface between the temporal regions and as far forward 

 as the interior part of the orbits, the surface over each orbit some- 

 what convex. Thenceforward to the tip of the muzzle, the profile 

 is somewhat convex from side to side, with a steep declivity on each 

 side in front of the orbit. The nares are rather large and oval, oi 



Fig. i8. — Seymouria baylorenis. Skull, 

 from above, one-half natural size, n, nasal; 

 Z, lachrymal; ^/, prefrontal; /lo/, postf rental ; 

 fr, frontal; it, intertemporal; st, supratem- 

 poral; do, dermoccipital; t, tabulare. 



