Professor R. Buycl-Jiai'df — On Ilyperodapedou Gordoni. 533 



The second specimen, disclosing impressions of the skin, is that 

 which supplied Huxley with the type for tab. xxvii, fig. 2. I have 

 been able to detect some smaller scales on this near the remains of 

 the caudal vertebrte, but not so clearly to be seen as in the other 

 example. 



I cannot conclude my account of Hyperodapedon without making 

 a few remarks on the systematic position of the Ehynchosaurians. 

 Although in the beginning of Huxley's second treatise he strongly 

 supports the theory of an intimate relationship existing between this 

 extinct group and the living Sphenodon, his conclusions, however, 

 are that they have only the following characters in common with 

 each other : — 



1. A prgemaxillary rostrum. 



2. A longitudinal series of palatine and maxillary teeth, of which 

 the posterior ones receive between them the mandibular row. 



3. An abdominal sternum. 



4. Absence of procoelous vertebraa in the prjesacral portion. 



Of the foregoing characters, number 1 breaks down at once, being 

 based upon a supposed identity of origin in two totally distinct 

 structures ; and the second no less so, as will have been seen in our 

 previous discussion. There remain only the third and the fourth 

 points, upon which it would be futile to base characters for the 

 establishment of a closer relationship between them. 



Von Zittel, too, ascribes to the Ehynchosaurians affinities with 

 Sphenodon, and places them nearer the latter than to the remaining 

 groups of Rhynchocephalians, as does also Smith Woodward. 



Boulenger unites the Proterosauridai with the Palasohatteridge to 

 form his Proterosauria. Some of the characters which he assigns 

 to this group are shared also by the Ehynchosaurians, such as the 

 flattened bone composing the pelvis, and especially the opisthocoelous 

 vertebra of the Proterosauridaa. The Ehynchosaurians and the 

 •Ohampsosaurians are brought under one heading too, with the latter 

 of which, except through convergence of similarities, they have 

 really nothing in common. For the reasons mentioned, then, the 

 classification as proposed cannot be said to be wholly satisfactory. 



Eecently Fiirbringer brought to a conclusion his comprehensive 

 systematic treatise on Eeptiles, wherein, following Baur, he 

 separates Hyperodapedon from Rhynchosmiriis, and places the family 

 Hyperodapedontidfe near that of Proterosauria, and the Ehyncho- 

 saurida3 with the Ehynchocephalia vera. I can only follow the 

 views of these authors in so far as they are restricted to the closer 

 relationship existing between Hyperodapedon and the Proterosaurida?, 

 and on account of its being already connected with the latter by the 

 possession of opisthocoelous vertebrae. Otherwise I consider a 

 separation of Hyperodapedon from lihjnchosaunis entirely erroneous, 

 and I can find no apology for it on the part of these authors, except 

 in the insufficiency of the published materials on which they based 

 their conclusions. 



After what has been stated as to the dentition and the characters 

 of the skull of Hyperodapedon, there exists no further ground for 



