Feet. 



Inches. 



Lines 



2 



2 











10 











7 



6 











9 







1 



4 







8 



6 







7 











14 







its 



3 



8 







2 



8 



ir 







3 



6 







3 















8 



CROCODILIA. 31 



The more entire fossil skull in question presents the following dimensions : 



Total length from the hindmost part of the lower jaw 

 Breadth between the articular ends of the tympanies 



Do. across the orbits ..... 



Do. of the intertemporal space 



Do. of the interorbital space .... 

 From the articular end of the tympanic to the orbit 

 From the occipital condyle to the orbit . 

 From the orbit to the external nostril 

 Breadth of the cranium five inches in advance of the orbits 



Do. across the external nostril 

 Depth of the lower jaw at the vacuity between the angular 

 and surangular ...... 



Length of that vacuity ..... 



Breadth of the base of one of the larger maxillary teeth 



This remarkably fine fossil skull, which is figured one third of its natural size in 



T. II, fig. 1, presents proportions which come nearest to those of the Crocodilus 



acutus, being longer in proportion to its basal breadth than in the Crocodihs Suchus, in 



which the diameter between the articular ends of the tympanis (28) is just half the length 



of the entire skull. The interorbital space in the Crocodilus toliajncus is relatively 



narrower and flatter than in the Croc, acutus or Croc. Suchus, and the facial part of the 



skull becomes narrower before the expansion of the upper jaw, at the figure lo, than it 



does in either of those species. The narrow elongated nasals on which the figure is is 



placed, extend forwards to the external nostril (22), as in the true Crocodiles, and the 



alveolar border is festooned as is shown in the side view in T. II A. The teeth 



22 22 



are ^ — —=84 in number : they are more uniform in size, and more regularly spaced 



than in the recent species above cited, and resemble in this respect the teeth of the 

 Crocodilus Scldegelii of S. Muller, which is from Borneo. The extent of the symphysis 

 of the lower jaw is greater in the Crocodilus toliapicus than in the Croc, acutus, and still 

 greater than in the Croc. Suchus; the Sheppy species in this respect more nearly 

 resembles the living species from Borneo above cited. 



Crocodilus champsoides, Owen. Tab. III. (Tab. II, fig. 2 ?) 



Syn. Crocodile de Sheppy (?), Cuvier. Loc. cit. 



Crococilcs Spexceri, or " Crocodile with a short and broad snout" (?) Bucldand. 

 Bridgewater Treatise, vol. ii, pi. xxv, fig. 1 . 



The fossil skull already described establishes the fact of the existence of a true 

 Crocodile in the London Clay at Sheppy, but not of a species with a short and broad 

 snout ; the present specimen equally demonstrates the presence at the earliest period 

 of the Tertiary geological epoch of Crocodilia with those modifications of the cranial 



