Geological Society of London. 377 



was also quite as far back in the skull, and the quadrate bone also presented 

 curious analogies, so much so as to be almost identical. The sutures presented 

 chai'acters similar to those exhibited by immature birds ; and he thought that 

 the separation of the bones in this example showed affinities to the anserine 

 type. He was quite prepared to regard the fossil as that of a bird rather than of 

 an Omithosaurian. He inquired as to the character of the palatal bones. 



Mr. Charlesworth inquired as to the light in which this discovery would be re- 

 garded by evolutionists. 



Prof. Owen briefly replied. 



3. " Contribution to the Anatomy of Hypsilo'phodon Foxii, an 

 Account of some recently acquired Eemains of this Dinosaur." By 

 J. W. Hulke, Esq., F.RS., F.G.S. 



After referring to Professors Owen and Huxley's descriptions of 

 the Mantell-Bowerbank skeleton in the British Museum, and to the 

 paper by the last-named gentleman on the skull of this Dinosaur 

 read at a meeting of this Society in 1870, the author communicated 

 details of its dentition, the form of its mandible, and that of the 

 cones of the shoulder and fore limb, and of the haunch and hind 

 limb, hitherto imperfectly or quite unknown. The resemblance to 

 Iguanodon is greater than had been supposed, but the generic dis- 

 tinctness of Hypsilophodon holds good. 



Discussion. — Prof. Owen remarked that palseontologists generally were in- 

 terested in obtaining such additional evidence of the generic characters of Iguano- 

 don as Mr. Fox's valuable discovery of the skull and other remains of the small 

 species in the Isle of Wight Wealden might supply ; but such desirable informa- 

 tion, especially as regards the cranial structure of the herbivorous Dinosaurs, is 

 shut out if those remains are shown to belong to a distinct genus. In the paper to 

 that end in the 'Quarterly Journal' for 1870, p. 3, the only teeth of the so-called 

 Hypsilophodon known to the writer, were those of the upper jaw, and these were not 

 entire ; the portion of crown answering to the serrated portion in Igicanodon was 

 worn away. Mr. Fox was therefore justified in rejecting Professor Huxley's genus 

 Hypsilophodon, although he might believe the statement that such serrations were 

 characteristic of the teeth of Iguanodon, especially when emphasized by the phrase 

 " so characteristic " ; the fact being, however, that marginal serrations characterize 

 the apical half of the crown in the Dinosaurian genera Scelidosaurus and Echinodon 

 as in Iguanodon. What are truly characteristic of the upper molars of that 

 herbivorous Dinosaurian are the ridges on the outer surface of the crown, which 

 ridges, being also present in Fox's Iguanodon, and supposed to be peculiar thereto, 

 suggested to Professor Huxley the term Hypsilophodoti. But the lower molars of 

 Iguanodon are equally ridged, but on the opposite side to those above, viz. the 

 inner side ; and the marginal serrations exter^d nearer to the base of the crown. 

 Now the lower molars of the small Iguanodon, also found, with the mandible, by 

 Mr. Fox, show this generic character, and vindicate the taxonomy of their dis- 

 coverer. We may rest assured, therefore, that the sloping edentulous symphysial 

 part of the mandible of the great Iguanodon had a downbent edentulous part of 

 the premaxillaries applied to it, such as the fore part of the skull of Iguanodon 

 Foxii exhibits. Without a knowledge of the characters of both upper and lower 

 molars of this small Iguanodon, no one in quest of the tnith of the matter could 

 affirm "that the teeth of this reptile were perfectly distinct from those of Iguanodon 

 Mantelli.'''' In the last plate of Prof. Owen's 'Monograph' for the forthcoming 

 volume of the Palceontographical Society, the mandible and mandibular teeth are 

 figured, and he had hoped to have received a proof to show to the meeting. The 

 mandibular teeth exhibited by Mr. Hulke were identical with those previously dis- 

 covered by Mr. Fox. In the ' Monographs ' the evidence will be found of the 

 specific, but not generic distinction of Mr. Fox's small Dinosaur from the large 

 Iguanodon Mantelli. 



4. "On the Glacial Phenomena of the 'Long Island,' or Outer 



