148 BRITISH FOSSIL REPTILES. 



Fortunately portions of two vertebrae are included in the mass of matrix still 

 adherent to the skull of Plesiosuchus. 



The first is a centrum of a mid- or post-dorsal vertebra (PL 20, fig. 3) lodged 

 in that part which obscures the base of the skull j it gives a length of oj inches ; 

 a vertical (posterior) breadth of 3 inches ; the transverse breadth seems not to 

 have exceeded 2 inches at the middle of the centrum. The preserved portion of 

 the base of the neural arch shows that the parapophysis had disappeared or risen 

 into confluence with the diapophysis, indicating the region of the spine from which 

 this vertebra has been derived. The character of the terminal articular surfaces 

 of the centrum removes this form of mesozoic Crocodile from the tertiary or 

 neozoic genera. Both surfaces are slightly concave, the fore one nearly approaching 

 to flatness. 



The degree in which the skull conforms to the proportions characteristic of 

 Cuvier's genus Grocodibis proper,'^ difi"erentiates it from the gavial-like genera 

 Teleosaurus and Steueosaunis, and the narial character above referred to more 

 decisively separates it from the latter, with which it has been confounded. I am, 

 therefore, constrained to append a name to the extinct genus which the Kim- 

 meridgian specimen represents, retaining the specific name applied to it by Mr. J. 

 "W. Hulke. I regret that having to record it, agreeably to the wish of my friend 

 Mr. Mansell Pleydell, in the concluding volume of the present Work, with con- 

 sequent unavoidable delay, gave the opportunity of a feUow-labom^er in Reptilian 

 PaliBontology to make the specimen known, and, in anticipation, to append to it a 

 generic name, which if applicable, I should have felt bound to retain." 



A second vertebra includes, with part of the centrum, the neural arch and 

 spine. The latter shows its obtuse free termination. The total height of this 

 vertebra is 9 inches ; that of the neural arch, spine inclusive, is 6^ inches ; the 

 neural spine along the fore part is 4 inches ; along the hind jiart from the base of 

 the postzygapophyses it measures 3 inches ; the thickness of the spine is 1 inch ; 

 the broad base of the broken diapophysis is 2 inch.es. This process projects from 

 near the base of the neural spine. The vertebral characters bespeak a platycoelian 

 Crocodile of great power, in concordance with the formidable array of teeth. 



The length of the maxillo-premaxillary alveolar tract (PL 20, fig. 2) is 1 foot, 

 8^ inches ; it includes 16 teeth on each side, of which 3 are supported by the pre- 

 maxillary, and the rest, after an interval of 9 lines, by the maxillary bones. Of 



' As exemplified in Crocodilus acuius, torn, cit., p. pi. i, fig. 3. 



2 " A closer examination lately made by Mr. Davies, sen., of the fossils presented to tLe British 

 Museum last year by J. C. Mansel, Esq., has led to the identification of a large Crocodilian head — this 

 head had been previously put aside as Pliosaurian " (Hulke, ' Quarterly Journal of the Geological 

 Society of London,' vol. xxvi (1S70), p. 167). 



That this collection included Pliosaurian remains from the same Kimmeridgian bed is true ; but 

 that the Crocodilian head was referred by any authority of mine to the Sauropterygia is incorrect. 



