56 Mr. G. A. Bouleuger. [Apr. 29, 



between the palatines and the vomers at some distance behind the 

 prjemaxillaries. Doubts have been thrown on Huxley's interpretation 

 of the outer toothed bone of the skull, and it is important to settle the 

 question of its identification. The new material has convinced the 

 author that the teeth in the upper jaw are borne by both the maxillary 

 and the palatine, as stated by Huxley. The fossil shows well the 

 elongate rhomboidal vacuity between the pterygoid, ending at the point 

 where they converge before diverging again towards the quadrate, to 

 the massive anterior branch of which they are suturally united. 



As may be seen from the annexed restoration, the palate of 

 Hyperodapedon bears great resemblance, in its general structure, to that 

 of the living Sphenodon, the principal differences, apart from the denti- 

 tion, residing in the smaller bony roof of the mouth and the narrower 



II. STENOMETOPON TAYLORI, G. et sp. nn. 



This name is proposed for a considerable portion of a skull of a 

 Ehynchocephalian, closely related to Hyperodapedon, and belonging to 

 the same family, Khynchosauridse. Its length is 177 mms. and its 

 greatest width 160. One of the most striking features of Hypero- 

 dapedon as compared with its New Zealand ally, SpJienodon, resides in 

 its much broader and more massive skull. The skull of the new 

 Ehynchocephalian, although agreeing in its general structure with 

 that of Hyperodapedon, is not broader and hardly more massive 

 than that of Sphenodon, from which it differs, however, very much 

 in shape. The rostrum has quite a different direction from either 

 of these skulls, the tusk-like prsemaxillaries, instead of being bent 

 downwards into recurved processes, are directed forwards in a 

 gradual slope from the frontal region to their extremities, which 

 project beyond the turned-up extremities of the mandibular rami. 

 This is practically the reverse of the condition in Hyperodapedon, 

 where the strongly curved prsemaxillary " tusks " are received between 

 the outwardly directed rostral processes of the mandible. Nasal bones 

 are absent. 



As in Hyperodapedon, the nasal aperture is single, but, in accordance 

 with the shape of the prsemaxillaries, it is more elongate, its length 

 being to its width as 2J : 1 ; its posterior border extends to the level 

 of the orbits, which are entirely directed upwards. The inter-orbital 

 region is narrow, especially behind. The supra-temporal f ossse are 

 very large, separated from the orbits by the narrow post-orbital arch 

 and from each other by the sharp median crest of the parietals. The 

 latero-temporal fossa is kidney-shaped and proportionately larger than 

 in Hyperodapedon, but smaller than the supra-temporal fossa. The 

 maxillary bone is deep and nearly vertical, with an oblique ridge 



