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consist of a body of compact dentine, forming a crown covered by a coat of 

 enamel, and a root invested by a moderately-thick layer of cement. One root 

 slightly enlarges, or maintains the same breadth to its base, which is deeply 

 excavated by a conical pulp cavity, extending into the crown, and is commonly 

 either perforated or notched at its concave or inner side." 



You will observe that the same characteristic features occur also in the 

 teeth of the skull under review : — 



The crown covered with dentine, ceases about a quarter of an inch from 

 the jaws, the lower part of the cement forming a well defined line running 

 parallel with the jaw bone. 



Mr. Triphook has given to the root of the teeth a darker tint, in his 

 drawing, than exists in the original, where it has almost the same colour 

 as the stone in which it is embedded. Only a slight rise on the surface 

 of the stone indicates where the more perishable lower parts of the teeth were 

 situated. 



It is scarcely necessary for me to observe that I am labouring under great 

 difficulties, in having no library of scientific books at my command to refer to, 

 so as to be able to ascertain if similar Saurian remains have been discovered 

 anywhere else, and I may add, that, generally, books of that nature are too 

 costly for individuals to jjurchase. However, from the data at my command, 

 I may state that the skull under review belongs to an animal of the sub-order 

 Crococlilia, called Amphicoelia by Professor Owen, and which includes, 

 among others, the genera Teleosaurus and Mystriosaurus. 



This sub-order is called Amphicoelia (capped on both ends) from the 

 peculiar character of the vertebra?, the vertebral body being concave on both 

 sides ; they, therefore, differ greatly from the existing Crocodilians, which have 

 a much more perfect arrangement of the vertebral column, and of which I 

 shall speak in the sequel. The Amphicoelia, in respect to the vertebral 

 body, have therefore a more fish-like character than the existing crocodiles. 



The same eminent comparative anatomist states, that the vertebral 

 surfaces of these Crocodilians were slightly concave, in order to enable them 

 to make greater progress through the water ; and that the hind limbs were 

 therefore relatively stronger than the fore limbs. 



From the nature of the deposits in which the remains of the Amphicoelia 

 are found, we must conclude that they were marine animals. 



The numerous vertebrae in the collection of Mr. Hood are, — with the 

 exception of one, of which I shall afterwards speak, — all slightly bi-concave, 

 and therefore agree with the Teleosaurian character. Amongst them are 

 .fourteen larger ones, still connected, which, in the average, are 2^ inches long, 

 by 4 inches high ; over them, and in a reversed position, lie five caudal 

 vertebra?, very long and slender ; also a great many other bi-concave vertebrae 

 were found, which are very remarkable, as being nearly twice as broad as high, 

 some of them are 3 inches broad, and If inches high. 



As far as I know from all the Saurians which have been described, only 

 Plesiosaurus, and Pliosaurus in a minor degree, have this characteristic 

 feature. 



Mr. Hood, some ten years ago, took, from the same locality, a collection 

 of Saurian bones to England, which were described by Professor Owen as 

 Plesiosaurus australis* Unfortunately, I have never had an opportunity of 



* The specimens referred to ' ' consisted of two vertebral bodies or centrums, ribs, and 

 portions of tbe two coracoids of the same individual, all in the usual petrified condition of 

 Oolitic fossils. Their matrix was a bluish-grey clay-stone, effervescing with acid ; the 

 largest mass contained impressions of parts of the arch and of the transverse processes of 

 nine dorsal vertebrae, and of ten ribs of the right side. Portions of five of the right 

 diapophyses and of six of the ribs remained in this matrix. The bones had a ferruginous 



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