WEALDEN DINOSAURS. 369 



The ossified pulp exhibits the parallel concentric layers of the ossified matter 

 surrounding slender medullary canals, and interspersed with irregular elliptical 

 radiated cells, affording the usual characters of the texture of the bone in the higher 

 reptiles. 



From the form and structure of these teeth, it may be inferred that they have 

 belonged to a Dinosaurian reptile ; not so strictly phytiphagous as in the Iguanodon, 

 but probably having a mixed diet. 



In reference to the size of both the fragment of jaw and of the teeth, there is about 

 the same proportion between them and the known remains of the Hylseosaurus, as 

 between the jaw with teeth of the Iguanodon and the vertebra; and limb-bones of that 

 colossal Dinosaur. The structure of the osseous substance of the portion of jaw 

 figured ni PI. 39, closely accords with that of the known bones of the Hyla^osaurus. 



Having, therefore, demonstrated that the above-described mandibular and dental 

 fossils of the Wealden do not appertain to the Iguanodon, nor to the Cylindricodon, it 

 has appeared to me more to the interests of pateontology to refrain from adding to its 

 catalogues a new name, which at present could signify nothing but the bare possibility 

 that the grounds for approximating the fossils in question to the Hylccosaurus may 

 prove not to be valid. 



Dermal Scutes. 



Unequivocal evidence that a dermal skeleton, analogous to that in the recent 

 Crocodiles, was developed in the Hyteosaurus, has been afforded by the discovery of bony 

 scutes in the mass of petrified vegetable matter removed in clearing the portion of the 

 skeleton first described. Some of these detached bony plates still adhere to the caudal 

 vertebrae, and may be observed to decrease in size as they approach the end of the 

 tail (PI. 41, fig. i, i, i). From their form, which is elliptical or circular, and from the 

 absence of any surface indicating the overlapping of an adjoining scute, it may be 

 inferred that the bony plates in question studded in an unconnected order the skin of 

 the Hylseosaur. The diameter of the largest of these scutes does not exceed 3 inches ; 

 the smallest present a diameter of 1 inch. They are flat on the under surface, convex 

 with the summit developed into a tubercle in the smaller specimens, but which is less 

 prominent in the larger ones : the outer surface is studded all over by very small 

 tubercles : the inner surface presents the fine decussating straight lines, which I 

 have described as characterising that surface, in the scutes of the Goniopholis.* 



By the kindness of Dr. Mantell, I was favoured, when preparing my ' Report on 



* 'Reports of British Association,' 1841, p. 71. 



