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The fragment of the upper jaw which has escaped destruction is 

 about six inches and three-quarters long-, showing a raised, arched 

 palate, with the alveolar borders, which are somewhat depressed 

 outwardly ; the alveoli on each side are exposed, one containing 

 the base of the tooth, showing its pulpous centre. Of the two 

 portions of the lower jaw which have been rescued, one is thir- 

 teen inches long, with thirty-four alveoli, eighteen on one side 

 and sixteen on the other, the alveolar region being slightly in- 

 clined outwards. The palatal surface is flat ; the other portion is 

 nine inches and three-quarters long, and appears to be broken away 

 above the symphysis; the non-bearing portion of the ramus is 

 eight inches long, and two-and-half inches at its greatest depth, 

 The only other fragment of the lower jaw is its articulare, about 

 four-and-half inches long, and, unlike the modern members of 

 the order, is not anchylosed to the jaw. The skull, as has been 

 already mentioned, is flat ; it is ten-and-half inches wide, and 

 four-and-half inches deep, including the horizontal paroccipital 

 ridges ; its posterior end shows a hemispheroid condyle, two-and- 

 half inches in basal diameter; the foramen magnum is transversely 

 elliptic, one and two-eighths of an inch across. Like the rest of 

 the genus, the parietal bone forms a narrow longitudinal ridge, 

 surmounting the mastoideum, of which much is lost ; below it is 

 the orifice for the passage of the auditory nerves ; the tympani- 

 cum, with which the pterygoideum combines in the formation of 

 this passage, is lost, and only a portion of the latter remains. 

 The quadrangular upper occipital is united on its upper part to 

 the parietal, and on each side by the two strong lateral occipitals. 

 The skull has the characteristic narrowness of the temporal 

 region, and the lateral orbit (which marks Geoffrey St. Hilaire's 

 sub-genus Steneosaurus), peculiarities, with some others, remarked 

 by Cuvier at the commencement of the present century, in two 

 species from the Oxford clay at Honfleur, and the Kimmeridge 

 clay at Caen, and differing from the usual crocodilian type, one 

 with a long snout " Tete a museau plus alonge;" the other with 

 a shorter snout, "Tete a museau plus court," the former of 

 which M. Deslongchamps identifies as Steneosaurus Edwardsii. 

 Cuvier saw their gavial affinity in the symphysis of the lower 



