ART. 2a. AN EXTINCT VARANID LIZARD GILMORE. 9 



ence detected is that the lower posterior extremity of the fossil is 

 more slender and tapering. It is pierced by a number of foramina 

 that form a row slightly above, but parallel to the dental border. 

 The sloping superior border anterior to where it joins the perfrontal 

 forms the outer boundary of the anterior nares. This border turns 

 inward toward the median line posterior to its anterior extremity, 

 but the anterior portion of the bone is missing. 



The right maxillary contains eight teeth and there are spaces for 

 five more, making 13 teeth within a space 35 mm. long. The same 

 space in Varanus contains only nine teeth. It is estimated that the 

 missing portion would have carried two, possibly three more, so that 

 in all the maxillary of Saniwa would have had at least 15 teeth, prob- 

 ably more. Because of the fragile nature of the 

 bone and teeth no attempt has been made to 

 free the internal or palatal side from the matrix. 

 Posteriorly this bone certainly articulated with 

 the palatine, ectopterygoid, prefrontal, and lach- ^ „ „ 



^ ' ^ ''^ •ii'i ^"^- ^- — Right post- 



rymal, and probably also with the jugal. frontal of saniwa 



Postfronfal— The postfrontal is a moderate- f,''^''lf'' \, ^!,'^^- 



' -111- 11 Type, Cat. No. 218.'), 



sized trihedral bone, articulated by its expanded u.s.n.m. natural 

 cranial end to the frontal and parietal by a «'^^ Viewed from 



^ '' ABOVE. p.f., CUPPED 



cupped articular area between the divergent an- surface which 

 terior and posterior branches (see p.f., fig. 7), articulates about 



^ '' 11 equally with the 



that fits in under and along the outer borders lateral projections 

 of these bones at their lunction. On the pos- °^ '^^® parietal and 



•' , . . ^ FRONTAL. 



terior side of the pointed distal projection a 

 roughened striated surface indicates the sutural contact of the post- 

 orbital, which in Saniwa exists as a distinct element. The left post- 

 frontal and postorbital were found articulated (fig. 8), the suture 

 distinctly shown, so that the manner of their articulation may be 

 considered as absolutely determined. In all of the illustrations of 

 the Varanus skull ^ and in three of the four skulls of this animal now 

 before me the postfrontal-postorbital complex appears as a single 

 bone. It is called postfrontal in all the illustrations of the F«ranw.<? 

 skull, there being no mention made of the presence of a postorbital. 

 However, on the ventral side of the right postfrontal of the skull 

 Varanus (Cat. No. 29408, U.S.N.M.), the suture between it and the 

 postorbital is visible under the glass. This suture takes essentially 

 the same course as in the fossil specimen. Probably in a juvenile 

 specimen the division between these two elements would be more 

 clearlj^ indicated. It is evident they coalesce early in life, so that in 

 adult specimens all traces of the sutures are obliterated. 



» Gadow, H. Amphibia and Reptilia, 1901, p. 542, fig. 138. Gadow recognizes these 

 elements as the fused postorbital and postfrontal. 



